This article is about a robotic space mission to Jupiter. This article is about the mission; there is a separate article about the spacecraft itself.
Hawkeye7(discuss) 20:59, 31 March 2024 (UTC)reply
UC
Very much coming in as a non-expert here, but it looks like a cracking article and at least gives me the illusion that I can understand what is going on. UndercoverClassicistT·
C 18:29, 1 April 2024 (UTC)reply
gravitational assist flybys: should this be gravitationally assisted flybys, as the first two words modify the third? I see no hits on Google Books for this precise phrasing.
It seems that "gravity assist flyby" is the correct scientific term
[2], so standardised on that.
Hawkeye7(discuss) 19:57, 1 April 2024 (UTC)reply
It launched the first probe into Jupiter: suggest The spacecraft launched to clarify that "it" isn't strictly the programme.
Jupiter's atmospheric composition and ammonia clouds were recorded. Io's volcanism and plasma interactions with Jupiter's atmosphere were also recorded: any way to avoid the slightly clunky repetition of were recorded?
Suggest linking "encounter", as it has a more specific meaning in this context than its everyday loose one.
Added a link to the Wiktionary entry (which I just created): "The period of a space mission during which it carries out its data-gathering objectives".
There was also concern about the effects of radiation on spacecraft components, which would be better understood after Pioneer 10 and Pioneer 11 had conducted their flybys. These indicated that the effects were less severe than feared: the tenses are a bit confusing here. How much time has passed between the two sentences? I'd suggest something in the middle to the effect of "these took place on [date] and indicated..."
who had headed the Mariner and Voyager projects: I'm not clear on the logic as to when names like Mariner and Voyager are italicised, but it seems to be inconsistent in this paragraph.
Longer travel times meant that components would age: well, yes, but I suppose the problem was that they would wear out with age? Things simply becoming older isn't necessarily a problem.
the onboard power supply and propellant would be depleted: is this quite true? For the first part, perhaps, but wasn't the point of the gravity assists that the overall mission would require less delta-v (and so less propellant) than a mission that didn't use them?
The onboard propellant is only used for inflight maneuvers, so gravity assist maneuvers would require more of them.
Hawkeye7(discuss) 18:48, 3 April 2024 (UTC)reply
Some of the gravity assist options also meant flying closer to the Sun, which would induce thermal stresses. However, the IUS was constructed in a modular fashion, with two stages: I'm not sure I see the point of the however here -- what's being contrasted? It sounds like we've just discussed reasons why the IUS was a bad component for this mission, and are now about to discuss reasons why it was a good one: could that be made clearer and more explicit?
Reworded the paragraph, and got rid of the "however".
Hawkeye7(discuss) 18:48, 3 April 2024 (UTC)reply
An important decision made at this time by Ames and the JPL was: a bit mealy-mouthed: better as Ames and the JPL decided...? Always better to show, not tell, that it was important, and we don't (in this paragraph at least) really set out why this made a difference.
The paragraph does explain: This allowed it to take high resolution images, but the functionality came at the cost of increased weight.Hawkeye7(discuss) 18:48, 3 April 2024 (UTC)reply
In which case, as we've shown,
WP:PUFFERY et al would encourage us not to use the word important, but rather to let the facts speak for themselves. UndercoverClassicistT·
C 19:51, 3 April 2024 (UTC)reply
The IUS was not powerful enough to launch a payload to Jupiter without resorting to using a series of gravity assist maneuvers around planets to garner additional speed: could we rework the double negative: something like "to launch a payload to Jupiter, the IUS needed to use a series of..."? I would also stick a full stop after additional speed and then do something like "Most engineers regarded the use of such maneuvers as..."
The second, but not the first. I'm not sure what the "otherwise" at the start of the new sentence means: was there any scenario in which the IUS would be powerful enough to avoid using gravity assists? UndercoverClassicistT·
C 21:07, 3 April 2024 (UTC)reply
A three-stage might have worked; "otherwise" refers to the two-stage IUS. I thought this was clear enough, but emphasised.
Hawkeye7(discuss) 03:18, 4 April 2024 (UTC)reply
Casani solicited suggestions for a more inspirational name for the project, and the most votes went to "Galileo" after Galileo Galilei: in both cases, I find myself asking: [suggestions/votes] from whom?
a launch on Space Shuttle Columbia on STS-23 : the Space Shuttle (like the battleship New Jersey) -- unless this is the HQRS norm? I'd also clarify something like "the STS-23 mission".
Lifting Galileo and the IUS would require: in this and similar sentences, if they actually did the thing suggested, it's better in the indicative: Lifting G. and the IUS required....
As explained further on, they did not do it.
Hawkeye7(discuss) 04:12, 4 April 2024 (UTC)reply
By late 1980, the price tag for the IUS had risen to $506 million (equivalent to $1.714 billion in 2023). The USAF could absorb this cost overrun: I'm not totally clear on the relationship between NASA and the USAF in this project. Had NASA contracted the Air Force?
As explained earlier, the USAF was in change of the two-stage IUS, NASA of the three-stage one.
What saved it from cancellation was the intervention of the USAF: less verbose as the USAF intervened to save it from cancellation.
I fail to see the value, but changed as suggested.
Hawkeye7(discuss) 04:12, 4 April 2024 (UTC)reply
in reality, the antenna got stuck while in space and didn't open all the way: I know that brevity is important in a caption, but I don't think "got stuck" or a contraction are the right
WP:TONE. Suggest "the antenna's motors stalled, preventing it from fully opening", or similar. UndercoverClassicistT·
C 10:27, 3 April 2024 (UTC)reply
The problem was not with the motors, but with the antenna being stuck, probably vacuum welded in place. Re-worded to address the issue.
Hawkeye7(discuss) 18:48, 3 April 2024 (UTC)reply
Not sure about the revised but in reality the antenna could not open all the way: to me, that reads as if it was impossible for the antenna to open fully. UndercoverClassicistT·
C 21:07, 3 April 2024 (UTC)reply
Simplified the caption to "the antenna could not extend"
Hawkeye7(discuss) 03:18, 4 April 2024 (UTC)reply
I still think we have the same problem: it sounds as though the antenna wasn't extendable at all. How about "failed to extend", which makes clear that it should have done so? UndercoverClassicistT·
C 06:20, 16 April 2024 (UTC)reply
pressurized atmospheric entry probe to a vented one: it would be useful to know what these things are: perhaps clearer if we explain it by what the probe would or wouldn't do?
But the three-stage IUS was itself overweight: It's not a rule, as such, but most style guides would avoid starting a sentence with but. More importantly, if we do use but here, we're setting up some followup in which this additional weight prevented something from taking place, and that never comes, so the paragraph would read better with something like "Furthermore", "Additionally", or indeed nothing at all.
After digging through various technical documents, I have added a footnote: "The rated power level (RPL) is the power at which an engine can be normally operated. In the case of the Space Shuttle, the specification called for 27,000 seconds operation at 100 percent of the RPL, or 14,000 seconds at 109 percent of the RPL, which was designated full power level (FPL)."
Hawkeye7(discuss) 04:17, 21 April 2024 (UTC)reply
The second was that despite this, it was also more gentle than the IUS, as it had lower thrust, thereby minimizing the chance of damage to the payload.: grammatically, needs a comma before despite this, but then becomes quite a winding sentence. I would go with something like The second was that it had lower thrust, thereby minimizing the resultant forces on and therefore the chance of damage to the payload.
could damage the spacecraft's optics and possibly the spacecraft itself.: the optics are part of the spacecraft, aren't they? Suggest "and possibly other parts of the spacecraft", or even something like "other, more mission-critical parts of the spacecraft", "other parts of the spacecraft, particularly..."
reads from one memory location disturbed those in adjacent locations: not quite grammatical (what's the antecedent of those: grammatically, it should be reads, but you can't damage a read). The noun "reads" is also a little tricky to parse. Suggest "repeatedly reading data from a single data cell damaged the other data cells around it", or similar.
That's not the case here, though, as there's nothing called a "Shuttle-Centaur" (that is, a Centaur that is also a shuttle, as distinct from maybe a "Saucer-Centaur"). This is instead the example given of Wilkes-Barre, a single city named after two people, but Minneapolis–Saint Paul, an area encompassing two citiesUndercoverClassicistT·
C 08:38, 16 April 2024 (UTC)reply
We used a hyphen in the featured article, and it is used in the sources. The form with a solidus is also used in the sources.
Hawkeye7(discuss) 11:07, 25 April 2024 (UTC)reply
Reading around, I can see the case for a hyphen: happy with this. UndercoverClassicistT·
C 14:37, 25 April 2024 (UTC)reply
Had been holding off while Roy concluded his review: thanks for the nudge. More below. UndercoverClassicistT·
C 16:02, 14 May 2024 (UTC)reply
The section on Nuclear concerns seems very determined that there was no real reason why anyone should have been worried about the plutonium. Is this the consensus of the sources?
Yes, but the sources are written by experts, who tend to have much less fear of radioactive substances than the general public.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
That's a fair point. Still, there are plenty of experts who have criticised the safety elements of other early-ish space missions and nuclear projects, so if none of them have really challenged the NASA narrative, I think
WP:DUEWEIGHT is satisfied. UndercoverClassicistT·
C 10:53, 15 May 2024 (UTC)reply
NASA concluded that the chance of a disaster was 1 in 2,500, although anti-nuclear groups thought it might be as high as 1 in 430. The risk to an individual would be 1 in 100 million, about two orders of magnitude less than the danger of being killed by lightning.: the first bit of this attributes both figures, recognising that there's a possible debate here, but the second doesn't: it's cited to NASA, however, who certainly had a horse in this race, so I don't think we can present it as straightforward, disinterested fact. If nothing else, the figure here surely depends on the overall probability of a disaster?
Changed to reiterate that this was NASA's opinion.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
This created a novel mission failure modality that might plausibly have entailed dispersal of Galileo's plutonium : could this be re-written in plainer English?
The risk to an individual would be 1 in 100 million, about two orders of magnitude less than the danger of being killed by lightning. The prospect of an inadvertent re-entry into the atmosphere during the VEEGA maneuvers was reckoned at less than one in two million: consistency advised under
MOS:NUM
an accident might have released up to 11,568 curies : not a common unit of measurement: can we contextualise that a bit? Would that be bad?
There is a link. The Three Mile Island accident released 2.5 million curies. Added a bit more from the risk assessment.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
There are some hyphens in page ranges in the footnotes (I noticed on note 74).
These are not page ranges. Hyphens are okay.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
Note 73 is Office of Space Science and Applications 1989, p. 2-24.. That's a page range, surely? Ditto 72: Office of Space Science and Applications 1989, p. 2-23.. We also generally use pp. or pages for a range. If p. stands for something other than "page", I think that would be wise to clarify (e.g. "section P" or similar). UndercoverClassicistT·
C 06:29, 15 May 2024 (UTC)reply
The document uses a page numbering system where pages have numbers like 2-4 and 4-18. In the text, this is documented by using the form p. 2{{hyphen}}4.
Hawkeye7(discuss) 19:41, 15 May 2024 (UTC)reply
Ah, gotcha. Happy here, then: it looks wrong (and might lead to well-meaning editors like myself trying to change it), but it's correct. You could perhaps use the |at= parameter rather than |p=, which would drop the "p." -- as e.g. 2-23 is really sort-of an abbreviation for "part 2, page 23"? UndercoverClassicistT·
C 20:48, 15 May 2024 (UTC)reply
There were fears that the spacecraft might be hijacked : presumably they would hijack the trucks, rather than the spacecraft, as the latter wouldn't be very easy to drive.
the appeal was therefore denied on technical grounds: is that technical grounds? It sounds like they denied it on substantive grounds: technical, to me, means that the proper procedures had not been followed, and so the issue was not considered, whereas the court did consider the issues but, as most appeals do, only had to determine that the original decision had been made legally and reasonably, not that it had been correct.
The source says: "The rejection of the appeal, by the D.C. Circuit Court of Appeals, was based on technical grounds and was not a ruling on the merits of the case."
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
In that case, we've got a contradiction here. If the reason for rejection was, as we've said, Chief Justice Patricia Wald wrote that while the legal challenge was not frivolous, there was no evidence that NASA had acted improperly in compiling the mission's environmental assessment (emphasis mine), that is a ruling on the merits of the case (that they weren't sufficient). Is this all from the same source: could you perhaps quote a bit more to see if we can see what's happened here? UndercoverClassicistT·
C 06:27, 15 May 2024 (UTC)reply
Re-worded to make it clearer that this was in the concurring opinion.
Hawkeye7(discuss) 19:41, 15 May 2024 (UTC)reply
343 kilometers (213 mi) orbit: singular and hyphenate (cf. a two-mile queue, a five-dollar note and a four-mile run).
Galileo's closest approach to Venus came at 05:58:48 UTC on February 10, 1990, at a range of 16,106 km: some inconsistency in the article about whether units are abbreviated or not.
Not per
MOS:HYPHEN: [hyphens are used] ... to link related terms in compound modifiers ... hyphens can aid ease of reading (that is, they can be ease-of-reading aids) and are particularly useful in long noun phrases: gas-phase reaction dynamics.UndercoverClassicistT·
C 11:12, 15 May 2024 (UTC)reply
As the spacecraft moved further from Earth, it also necessitated the use of the DSN's 70-meter dishes: not quite grammatical (the antecedent of it is the spacecraft, but the spacecraft didn't necessitate the use of the dishes: its movement did). Secondly, who were the other users of the dishes?
Not to me, I'm afraid, and it needs to be clear to readers who don't know much about astronomy, telemetry, and don't have an expert grasp of English. UndercoverClassicistT·
C 11:12, 15 May 2024 (UTC)reply
Earth's magnetic field causes the bow shock to occur at around 65,000 kilometers (40,000 mi) from its center, but Venus's weak one: weak magnetic field, or weak centre?
Magnetic field. Added, although it makes the text harder to understand.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
If you want it clearer, how about but Venus's magnetic field is weaker, causing the bow shock to occur nearly on the surface? UndercoverClassicistT·
C 06:31, 15 May 2024 (UTC)reply
plasma wave detector: hyphenate as a compound modifier.
It's not a proper noun: we're using the term for a thing that detects plasma waves. If we want to refer to a specific thing by the name of "plasma-wave detector", and so to make it a proper noun, we would need to capitalise, but we don't do that for other unique parts of a ship: the thrusters, the engines, the wings and so on are all lower-case. Sources may not hyphenate, but they may have their own house style, and don't have to follow the MoS: we do. UndercoverClassicistT·
C 11:09, 15 May 2024 (UTC)reply
Changed. But I am not changing it elsewhere.
Hawkeye7(discuss) 19:41, 15 May 2024 (UTC)reply
on 9 to 12 April and 11 to 12 May 1990: the prevailing style here seems to be MDY, so I'd switch to that.
Yes, it uses mdy. God knows why, as all the sources use the normal format.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
This was only 8 kilometers (5 mi) higher than predicted, and the time of the closest approach was only a second off.: I would cut both onlys as editorialising, possibly rephrasing slightly to e.g. "the time of the closest approach was within a second of what had been predicted".
That's up to the start of "Earth encounters": will be back once you've had a chance to look at this batch. I appreciate it's a lot: it's a big article that is saying a great deal and doing an admirable job of getting the nitty-gritty across while keeping it clear and engaging. UndercoverClassicistT·
C 16:02, 14 May 2024 (UTC)reply
Marching on:
energetic particles detector: you can probably guess this one: hyphenate (particularly useful here: it was the particles, not the detector, that were energetic).
by 35 meters per second: should we include an imperial conversion here (mph/fps) as we have for most other measurements?
Added. The purpose of the conversions is to render historic measurements in the sources into metric. Converting metric to imperial serves no purpose other than looking consistent.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
at a range of 960 km (600 mi) at 20:34:34 UTC on December 8, 1990. This was 8 kilometers (5 mi): there are other examples, but I'd advise consistency as to whether units are abbreviated or not (generally, per
WP:NOTPAPER, I'd suggest not, but there's an argument for not writing out "kilometers" in full if the word is coming up several times in a sentence or paragraph).
MOS:UNITNAMES: "In prose, unit names should be given in full if used only a few times, but symbols may be used when a unit (especially one with a long name) is used repeatedly, after spelling out the first use". Abbreviated.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
Normally they are only seen in September or October, but Galileo was able to detect them in December, an indication of damage to Earth's ozone layer: is it possible to explain this a little, perhaps in a footnote -- what does ozone layer damage have to do with these things appearing earlier?
Just another experiment taking advantage of an instrumented spacecraft having an encounter with Earth.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
I'm not following: what I'm asking for here is an explanation of how an indication of damage to Earth's ozone layer follows from Normally they are only seen in September or October, but Galileo was able to detect them in December. It's clear enough that this was an abnormal observation, but not clear how it indicated damage to the ozone layer. UndercoverClassicistT·
C 06:30, 21 May 2024 (UTC)reply
I'm not an atmospheric physicist, but added a one-sentence explanation.
Hawkeye7(discuss) 07:17, 21 May 2024 (UTC)reply
As I read it, it sounds as though these clouds would cause the damage, rather than being a sign or consequence of it: could we make that a bit clearer, if so?
The text says: "The NIMS was employed to look for
mesospheric clouds, which were thought to be caused by
methane released by industrial processes. The water vapor in the clouds breaks down the
ozone in the upper atmosphere. Normally the clouds are only seen in September or October, but Galileo was able to detect them in December, an indication of possible damage to Earth's ozone layer."
Hawkeye7(discuss) 19:20, 21 May 2024 (UTC)reply
I'm not sure we need the abbreviation of μmol/mol, as we don't ever use that unit again: on the other hand, glossing it to 'one part in a million' might be useful.
the scan platform acceleration on the spacecraft being slower than expected: this is slightly murky: do we mean that the scan platform wasn't able to move (accelerate) as quickly as the scientists thought?
It was not able to accelerate (change speed) as fast as expected.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
Thought so; would say it closer to that, then, as it's much clearer and conveys the same information. UndercoverClassicistT·
C 16:42, 18 May 2024 (UTC)reply
data acquired was to design laser downlinks: I think this should be was used to -- people designed the downlinks; the data didn't. No objection, but are we going for data as singular rather than plural?
I never use data in singular; I always use "datum". Corrected.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
I quite like the abbreviation template on HGA, but why is it there and not on any other abbreviations?
Another editor asked for it, given that the abbreviation was defined long before in the text.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
The two LGAa: this is probably the correct plural abbreviation (like LLB or pp. -- though I haven't seen a case where you decap the repeated initial), but it reads oddly: suggest perhaps spelling the abbreviation out on this occasion to avoid that?
The two LGAa were capable of transmitting information back to Earth, but since it transmitted its signal over a cone with a 120-degree half-angle, allowing it to communicate even when not pointed at Earth, its bandwidth was significantly less than that of the HGA, which transmitted over a half-angle of one-sixth of a degree, would have been: this is a long sentence: it's pretty clear up to would have been. Suggest something like than that of the HGA would have been, as the HGA transmitted....
"it looked like Galileo's only trip would be to the Smithsonian Institution.": this quote should be attributed in the text.
WP:INTEXT: " In-text attribution may need to be used with direct speech" but "should always be used for biased statements of opinion."
Hawkeye7(discuss) 20:01, 19 May 2024 (UTC)reply
Yes -- I think the combination of the quote's inherently unverifiable nature (who can disprove what "it" looked like -- that's not an empirical statement) and its strong, slightly sardonic authorial voice mean that here it really does need to be attributed. From another angle, the primary reason to include the quote, rather than a bland statement of fact like "there was a possibility that the mission would not take place", is that it is cleverly and engagingly written, and therefore it seems unfair to benefit from the author's skill and effort here while not crediting them as fully as we could. UndercoverClassicistT·
C 20:17, 19 May 2024 (UTC)reply
The reason no one had thought of it before was that the second encounter with Earth would not give the spacecraft any extra energy: the start of this sentence is verbose, and we should restate what "it" is in the new paragraph. Suggest "The VEEGA trajectory had not previously been considered because..."
I would swap the centre and left moon images around: most readers will read the left-hand one first, and it's odd that the middle one clarifies that it's of the moon when that one doesn't.
Image data collected was buffered and collected in Galileo's CDS extended memory. This represented 192 kilobytes of the 384 kilobyte CDS storage, and had been added late, out of concern that the 6504 CMOS memory devices might not be reliable during a VEEGA mission: I don't think we ever explain what CDS and CMOS mean. It's also been a while since we explained VEEGA: perhaps spelling it out, rewording it, or adding the abbreviation template would be helpful here.
Added definition of CDS, linked CMOS, added abbreviation template for VEEGA
while other data was compressed with variant of the Lempel–Ziv–Welch algorithm: data were, I think. Likewise The data collected on Jupiter and its moons was stored and, later, From subsequent analysis of this data
Two months after entering the asteroid belt, Galileo performed the first asteroid encounter by a spacecraft, passing 951 Gaspra , an S-type asteroid, at a distance of 1,604 km (997 mi) at 22:37 UTC on October 29, 1991 at a relative speed of about 8 kilometers per second (5.0 mi/s a long sentence with lots of piled-up clauses: suggest splitting into at least two.
covering about 80% of the asteroid: earlier we wrote expressed confidence that 70 percent of Galileo's science goals could still be met. -- advise consistency.
Several relatively flat planar areas were found, suggesting a catastrophic origin: can we rephrase a catastrophic origin to be clearer ("suggesting that the asteroid was formed when..."?)
Measurements of the solar wind in the vicinity of the asteroid showed it changing direction a few hundred kilometers from Gaspra, which hinted that it might have a magnetic field: grammatically, it could be either Gaspra or the solar wind.
I think it is pretty obvious, but changed "it" to "Gaspra".
Hawkeye7(discuss) 20:53, 20 May 2024 (UTC)reply
Galileo suddenly abandoned the observation configuration and resumed its cruise configuration: could amend spontaneously for suddenly to be clear that this wasn't the result of human input?
the legendary Dactyloi, mythical beings which lived on Mount Ida on Crete, after which the asteroid was named. Craters on Dactyl were named after individual dactyloi: we should be consistent as to whether Dactyloi is capitalised or not (it is in our article). You might also wish to use the English plural "Dactyls", as it's an easier jump from there to "Dactyl" for most readers.
after the legendary Dactyloi, mythical beings which lived on Mount Ida on Crete, after which the asteroid was named: slightly grammatically ambiguous as to whether after which has "the Dactyloi", "Mount Ida" or "Crete" as its antecedent.
Dactyl was the first asteroid moon discovered. Previously moons of asteroids had been assumed to be rare. The discovery of Dactyl hinted that they might in fact be quite common: this is certainly clear, but a little clunking: can we polish it for prose elegance?
Dactyl appeared to be an S-type asteroid, and spectrally different from 243 Ida, although it is also an S-type asteroid: is the antecedent of 'it Dactyl or 243 Ida? Grammatically, the former is most intuitive, though meaning-wise I think we want the latter: suggest a rephrase.
while it was en route, an unusual opportunity arose: this reads as a little bit pulp-journalism to me: is there any such thing as a usual opportunity in a mission that is inherently a one-off? I'd cut this sentence, personally, for tone.
We only need consensus to change the whole article to NASA dmy format.
Hawkeye7(discuss) 20:53, 20 May 2024 (UTC)reply
I'm not sure I understand what you mean. At the moment, the dating system is inconsistent: elsewhere, we have January 2 and 12, 1982, for example. Honestly, I'm willing to wear "NASA English" as a subset of AmerE that uses DMY dates, but we do need to pick one. UndercoverClassicistT·
C 20:56, 20 May 2024 (UTC)reply
The article currently uses mdy. I have changed the format of the dates in question.
Hawkeye7(discuss) 21:35, 20 May 2024 (UTC)reply
While Galileo was still a long way from Jupiter: any idea of how far?
When Galileo observed an impact in ultraviolet light, it lasted for about ten seconds, but in the infrared it persisted for 90 seconds or more: I'm not sure of the grammar here: the impact itself, by definition, lasted only a moment, but perhaps its traces persisted for longer?
Still need to do the last bit: will get to that when I can. UndercoverClassicistT·
C 19:36, 27 May 2024 (UTC)reply
Right, finishing off:
83 million kilometers (52×10^6 mi and following: not sure what the MoS is on this, but it's odd to mix standard-form and regular numeral notation: suggest "52 million miles", especially as we're not really in the sort of very big or very small numbers that really need SF.
I am fairly sure that it is MOS conformant, becuase it is generated by the conversion template, but dislike this form too. Just a matter of the correct incantation to get the outpuut right. Changed as suggested.
Hawkeye7(discuss) 22:53, 28 May 2024 (UTC)reply
The Galileo probe's project manager, Marcie Smith at the Ames Research Center, was confident that this role could be performed by the LGAs: I would clarify what this role was: we've just been talking about firing engines, which got me quite confused.
The dust particles were about the same size as those in cigarette smoke: could we give an actual measurement? This is good to get a feel, but I'm not sure many people would have a specific number in mind.
Usually you want the allegory. Added their approximate size.
Hawkeye7(discuss) 22:53, 28 May 2024 (UTC)reply
The existence of the dust storms had come as a complete surprise to scientists.: presumably, only when Ulysses encountered them; we should clarify that the existence of dust storms was unsurprising to the Galileo team.
data storage to the tape recorder for later compression and playback was absolutely crucial: cut absolutely: something can't be only a little bit crucial.
the radiation exceeded expectations, and nearly the spacecraft's design limits: purely for prose style, I think we need another verb after nearly: either exceeded again or a synonym.
Most robotic spacecraft respond to failures by entering safe mode and awaiting further instructions from Earth, but this was not possible for Galileo... because it would have taken too long for a signal to get there? Or had they just not added that feature? We later imply that it could, which means that we need some explanation for why it couldn't at this point.
The descent probe awoke in response to an alarm: awoke is perhaps a little anthropomorphic.
It is a technical term used in computer science. A
sleep (command) suspends execution until it is woken by an alarm.
Hawkeye7(discuss) 22:53, 28 May 2024 (UTC)reply
ammonia ice-particles : ammonia-ice particles (that is, particles of ammonia ice), surely?
ammonium hydrosulphide ice particles: by the same logic, endash after hydrosulphide. Is the British spelling of hydrosulphide intended? Sulfide is used elsewhere.
As it passed through Jupiter's cloud tops, it started transmitting data: grammatically, the antecedent of it should be the heat shield, but we presumably mean the probe as a whole.
The probe's seven scientific instruments yielded a wealth of information: at least to me, a wealth of information is a bit
WP:PUFFERY and slightly too idiomatic/flowery. Suggest showing rather than telling by just getting to what they yielded.
The implication was that the winds are not produced by heat generated by sunlight or the condensation of water vapor (the main causes on Earth), but are due to an internal heat source.: can we explain why this was a reasonable implication: presumably because Jupiter gets less energy from the Sun, being further away, yet somehow had faster winds, so the extra energy had to come from somewhere else?
No solid surface was detected (or expected) during the 156-kilometer (97 mi) downward journey.: does this really need to be said? It would have been huge news to find out that Jupiter had a solid surface, but I can't see that anyone, either then or now, would be remotely thinking of it as a possibility.
The probe detected less lightning... There was far less lightning activity than expected, only about a tenth of the level of activity on Earth. These two seem to go together, but are widely separated. Can we restructure to change that?
It orbits faster though, with a rotation period of 1.769 days: Not sure about the tone here: better and more formal as "However, it orbits more quickly..." (faster is an adjective, not an adverb, in formal writing).
More quickly is not used in formal writing, and Wikipedians deplore the use of "however".
Hawkeye7(discuss) 22:53, 28 May 2024 (UTC)reply
Where are you getting that "more quickly" isn't used in formal writing? I've never heard that "rule", and a quick ping through Google Books and JSTOR finds it in plenty of prestigious books, academic journals and so on. I've also never come across a MoS or other prohibition on "However": it's used twice in this article already. UndercoverClassicistT·
C 07:28, 29 May 2024 (UTC)reply
After a frantic effort, they managed to diagnose a problem that had never been seen before, and restore the spacecraft systems with just two hours to spare: a bit breathless (
WP:PUFFERY) in tone for me.
the flyby was very successful: in nearly all circumstances, I would advise cutting very, and would continue to do so here.
While such events were more common and spectacular on Io than on Earth, it was extremely fortuitous to have captured it: not sure this adds anything: I'd be more sympathetic if we could follow it with e.g. "because it only occurred once during the entire time-span of the mission" or something like that.
This time Galileo passed just 198 kilometers (123 mi) over the surface of Io. At this time, the spacecraft was nearly at the maximum distance from Earth, and there was a solar conjunction, a period when the Sun blocked the line of sight between Earth and Jupiter. As a consequence, three quarters of the observations were taken over a period of just three hours.: the "just"s, here (particularly) and elsewhere, read as
editorialising to me.
Unfortunately, a series of observations of extreme ultraviolet (EUV) had to be cancelled due to yet another safe mode event: likewise the unfortunately -- and another hyphen needed in safe-mode event
planetary scientist Margaret G. Kivelson, announced that Io had no intrinsic magnetic field, which meant that its molten iron core did not have the same convective: lose the comma after Kivelson. "Convective" is redlinked: is
Convection the intended target?
This time, Tvashtar was quiet: per
MOS:IDIOM, I would advise rephrasing to something that more explicitly says that the volcano was not erupting (it might have been doing so without making much noise).
Both of the sources say: "Tvashtar was quiet".
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
They might, but they don't have to follow
MOS:IDIOM: more to the point, if they use a creative idiom and we copy it wholesale when good alternatives exist, we're breaking (in a very small way)
WP:COPYVIO. We're allowed to take the facts from sources; we can't take the creative expression unless we present it as a quotation and/or attribute. UndercoverClassicistT·
C 07:27, 29 May 2024 (UTC)reply
I don't have the source in front of me, though I do have Google telling me that "Effusive eruptions are sometimes called 'quiet' eruptions". Is it absolutely unambiguous in the sources that the volcano was erupting, just not emitting a plume, other than the use of the word "quiet"? I'm not sure I can see in isolation that "the volcano was quiet" definitely means "the volcano was erupting effusively" rather than "the volcano was not erupting". UndercoverClassicistT·
C 21:37, 29 May 2024 (UTC)reply
The sources are online. Melzer (p. 254) says: "The Tvashtar volcano was quiet". This is sourced to
NASA. which says: "When Galileo sped past Io's north pole on August 6, scientists were watching for activity from a polar volcano named Tvashtar, which had been spewing a plume several hundred km high only seven months earlier. But Tvashtar was quiet."
Hawkeye7(discuss) 01:53, 30 May 2024 (UTC)reply
Our article on Tvashtar cites
this source, which makes it clear the volvcano was still erupting.
Hawkeye7(discuss) 01:58, 30 May 2024 (UTC)reply
I don't think it does: in fact, I see Streaks of light and dark deposits can be seen radiating from the central patera (volcanic crater), remnants of the now finished plume eruption, which says to me that it had finished. It does say that the volcano was still active, but that's not the same thing. Have I missed something on that page? UndercoverClassicistT·
C 07:42, 30 May 2024 (UTC)reply
"The Galileo spacecraft caught Io in the act of an active volcanic eruption on Februrary 22, 2000. Tvashtar Catena is a chain of calderas, collapse pits formed by volcanic eruptions. The active site of the eruption is visible on the left edge of the image, where infrared imaging sees the glow of a hot lava flow more than 60 kilometers long."
[4]Hawkeye7(discuss) 20:14, 30 May 2024 (UTC)reply
Although the project team worked hard to restore the spacecraft to working order, much of the hoped-for data was lost.: I'd consider cutting the first bit: this is already a very long article and section, and we surely take as read that they didn't sit back while their machine was broken?
Although the smallest of the four Galilean moons, with a radius of 1,565 kilometers (972 mi), Europa is still the sixth largest moon in the solar system: in the vein of some comments above, I'd cut still.
A "nontargeted" encounter is defined as a secondary flyby up to a distance of 100,000 kilometers (62,000 mi).: at a distance up to is more grammatical, I think. Not sure we need the quote marks: "a grandfather clock is defined as an expensive one in a tall wooden box" works fine.
Astronomer Clark Chapman argued that if we assume that a 20-kilometer (12 mi) crater occurs in Europa once every million years, and given that only about twenty have been spotted on Europa, the implication is that the surface must only be about 10 million years old.: the MoS discourages "we" in this kind of construction: suggest "argued that the surface of Europa must only be about 10 million years old, assuming..."
As I read it, the most obvious interpretation is that it contained magnesium, which I don't think is true or intended. UndercoverClassicistT·
C 07:25, 29 May 2024 (UTC)reply
Changed to "magnesium- and sodium-based salts" but note that "base" has the technical meaning of "cation" in this context.
Hawkeye7(discuss) 19:26, 29 May 2024 (UTC)reply
Since the surface temperature on Europa was a chilly −162 °C (−260 °F): that's rather below what most of us would call "chilly" (indeed, it's almost "big coat weather" up here): given the following sentence, these words can go with no loss.
Deleted. (It's not very warm here either.)
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
There was acrimonious debate among scientists over the thickness of the ice crust, and those who presented results indicating that it might be thinner than the 20 to 30 kilometers (12 to 19 mi) proposed by the accredited scientists on the Galileo Imaging Team faced intimidation, scorn, and reduced career opportunities: the chronology here seems important, but I have totally lost any sense of when this happened, or how long it went on for. Did this happen during the span of the mission itself? If not, suggest moving to a later section.
The article has switched from chronological to locational order, as Galileo returns to each Moon several times.
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
We are inconsistent about whether it's Canberra (This allowed Canberra and Goldstone to investigate the ionosphere of Europa or the Canberra (The Galileo project was able to secure 80 hours of the Canberra's 70-meter dish time.
This was the first time that a magnetic field had ever been detected on a moon contained within the magnetosphere of its host planet: does this really need all four citations?
Margaret Kivelson, the scientist in charge of the magnetometer experiment, felt that the induced magnetic field required an iron core: words for said are tricky, but felt here could perhaps cast the implication that she was working on intuition or vibes rather than professional knowledge and experience.
40 percent water ice: if we just said "ice", I don't think many readers would assume it was anything else. I think the link to
ice is an overlink.
Normally yes, but all mentions so far have been of ammonia icx.
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
NASA engineers were able to recover the damaged tape recorder electronics: hyphenate tape-recorder. On another note, there seems to be an extra line break after this paragraph.
The star scanner was observing a set of stars which included the second [[Magnitude (astronomy)]|magnitude]]: something is up with the formatting here.
The bit of wikitext with the square brackets at the end displays on the page -- you'll find it with ctrl-f. UndercoverClassicistT·
C 07:25, 29 May 2024 (UTC)reply
Delta Velorum is the brightest known eclipsing binary, brighter at maximum than even Algol.: Even is editorialising, but do I assume correctly that Algol was the previously brightest known eclipsing binary?
Delta Velorum is the brightest-known eclipsing binary, although Algol has a deeper minimum and is easier to observe visually. DEleted "even".
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
After the primary mission concluded on December 7, 1997, most of the mission staff departed, including O'Neil, but about a fifth of them remained. The Galileo orbiter commenced an extended mission known as the Galileo Europa Mission (GEM),: this is a good explanation of the GEM and GMM, which would have been much better before we got into those two moons -- we were using both of those terms quite freely, and I had rather little idea of exactly what and when we were talking about. Suggest restructuring so that this "Mission extension" section comes before what happened after the mission extension.
although it might seem wasteful to scrap a spacecraft that was still functional and capable of performing a continuing mission, Congress took a dim view of requests for more money for projects it thought had already been fully funded: this is quite strongly editorial, and needs to be rephrased to have a more neutral authorial voice.
It needs a fairly major rework: although it might seem wasteful to scrap a spacecraft that was still functional and capable of performing a continuing mission casts the strong implication that Congress were being wasteful; similarly, Congress took a dim view of requests for more money for projects it thought had already been fully funded casts them as fools, unable to see that the project had not in fact been fully funded. UndercoverClassicistT·
C 07:24, 29 May 2024 (UTC)reply
The project had been fully funded. NASA deliberately kept the price tag low in order to get funding in the first place, and there was a real possibility of the spacecraft failing before funds ran out. Deleted "it thought".
Hawkeye7(discuss) 19:26, 29 May 2024 (UTC)reply
That bit is better, but although it was wasteful to scrap a spacecraft that was still functional and capable of performing a continuing mission is still a problem. I'd be happier if someone (ideally within Congress) expressed this sentiment at the time, so we could say "although Rep. Stevenson of Ohio gave a speech in which she said...", "despite an open letter from 25 scientists arguing that it was..." or something like that. UndercoverClassicistT·
C 07:40, 30 May 2024 (UTC)reply
In order that scientists could determine whether or not native life forms existed before the planet became contaminated by micro-organisms from Earth,: this one needs a look. Firstly, whether or not is a tautology: whether is better. Secondly, as phrased, it implies that Mars has already become contaminated by microorganisms from Earth.
An alternative was the Prime Directive, a philosophy of non-interference with alien life forms enunciated by the original Star Trek television series that prioritized the interests of the life forms over those of scientists. : this doesn't seem to be relevant here, as we don't say that anyone proposed it for Galileo.
Still don't see it: I see Given the (admittedly slim) prospect of life on Europa, scientists Richard Greenberg and Randall Tufts proposed that a new standard be set of no greater chance of contamination than that which might occur naturally by meteorites, but it sounds like this is "new" relative to the 99.9% standard adopted in 1964. UndercoverClassicistT·
C 07:23, 29 May 2024 (UTC)reply
I think the numbered list in "Major findings" would be better and more MoS-friendly in prose.
NASA-ESA Outer Planets Study Team: endash, not hyphen.
Endashes are not being used for anything but page ranges. They cause more thgan enough trouble already.
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
They should be:
MOS:DASH asks for them in compounds when the connection might otherwise be expressed with to, versus, and, or between. UndercoverClassicistT·
C 07:21, 29 May 2024 (UTC)reply
I know it's not an article on Juno, but is there anything we can say about what that spacecraft observed: did or will it confirm, sharpen or change any of the findings from Galileo? Are any of its research tasks shaped by the experience of Galileo?
That's my lot on a first pass. The article is certainly a monumental piece of work, and I appreciated the occasional tours into more general areas of astronomy and science when they helped explain the specifics of the mission. UndercoverClassicistT·
C 21:08, 28 May 2024 (UTC)reply
AG
Reserving a spot.
Artem.G (
talk) 19:01, 1 April 2024 (UTC)reply
First comments:
Galileo Project managers table looks broken on mobile, I'd also suggest to move it from the lead.
Pravda? Works okay on my iphone. Where do you suggest moving it to?
Hawkeye7(discuss) 20:36, 1 April 2024 (UTC)reply
Nevermind, I think it's either android or chrome quirk.
Artem.G (
talk) 06:35, 2 April 2024 (UTC)reply
Following the approval of the Voyager missions - link
Voyager program
while the legal challenge was not frivolous - why frivolous is a red link?
Not sure how it became red. Possible page move.
Hawkeye7(discuss) 20:36, 1 April 2024 (UTC)reply
It was noted that the name was also that of a spacecraft in the Star Trek television show. - maybe something like "The name also belongs to a spaceship in the Star Trek series."?
The point is that this fact was acknowledged at the time.
Hawkeye7(discuss) 20:36, 1 April 2024 (UTC)reply
and the Space Shuttle main engines (SSME) running at full power—109 percent of their rated power level.[20] Running at this power level necessitated the development of a more elaborate engine cooling system.[28] - two questions. First: full power should be 100%, so is it correct to say "at full power" here? Maybe smth like "above its full power"? I don't know the right terminology here, so maybe I'm wrong. And second: why more elaborate cooling system was needed? The engines were not designed to work at full power?
nice, makes sense.
Artem.G (
talk) 06:40, 3 April 2024 (UTC)reply
but NASA hoped to be able to recoup some of this through separate completive bidding on the two. - I'm not sure I understand what's "separate completive bidding"
the experiment was considered a resounding success and the data acquired will likely be used in the future to design laser downlinks that will send large volumes of data very quickly from spacecraft to Earth. The scheme was studied in 2004 for a data link to a future Mars orbiting spacecraft.[90] - any updates on that? It's a bit strange to see future tense about data from 1992 experiment.
At the time it was written there was not, but in December 2023, NASA's
Deep Space Optical Communications experiment on the Psyche spacecraft used infrared lasers for two-way communication between Earth and the spacecraft. Added this to the article.
Hawkeye7(discuss) 21:01, 2 April 2024 (UTC)reply
Through the implementation of sophisticated technologies - what are these technologies? And does it mean that HGA was completely off, unable to transmit anything?
Data compression software. Changed to this, with a link. HGA was rendered space junk. made this clearer.
Hawkeye7(discuss) 21:01, 2 April 2024 (UTC)reply
a total power of about 10 zeptowatts - a power of 10 should be more readable
a 1980 suggestion that the results of Galileo could be distributed electronically instead of on paper was regarded as ridiculous by geologists - just curious - it means that previously all data received from spacecraft (ie. Voyager) was printed and not stored on a tape or a computer, right?
Voyager data was stored on 8-track magnetic tape, 9-track magnetic tape and paper tape.
Hawkeye7(discuss) 21:01, 2 April 2024 (UTC)reply
thanks, never thought about that!
Its shape was not remarkable for an asteroid of its size.[110] - what is a 'remarkable shape' for an asteroid?
maybe something like "dubbed Dactyl after the legendary Dactyloi, the Ancient Greek mythical race"? Though I agree that it's also not ideal.
Artem.G (
talk) 06:40, 3 April 2024 (UTC)reply
Dactyl appeared to be an S-type asteroid, and spectrally different from 243 Ida - type of Ida is not mentioned
and telemetry from the spacecraft, travelling at the speed of light, took 37 minutes to reach the JPL - it reads like the spacecraft itself is travelling at the speed of light. Suggest to change it to "transmitted at the speed of light"
Another opportunity to observe Io arose during the GEM, when Galileo flew past Io on orbits I24 and I25, and it would revisit Io during the GMM, on orbits I27, I31, I32 and I33.[155] - what're GEM and GMM? It's explain only in Mission extension, but should be explained at first mention.
Michael Carr, a planetologist from the US Geological Survey, argued that, on the contrary, the surface of Europa was subjected to less impacts than Callisto or Ganymede.[174] - what was his justification?
I agree with Tercer, the patch looks strange, even though it is from NASA website (and was there since 1996)
The image in the article is from a NASA site (
[10]) and therefore regarded as authoritative.
In Ganymede and Callisto sections, instead of real photos there are "The internal structure" images. I think real photos would suite the article better, and I'm not sure that internal structures (as pictured) were known during the project.
The article discusses composition, so the diagrams help the reader understand the text. But there is no reason we cannot have both. Added images.
Hawkeye7(discuss) 21:01, 2 April 2024 (UTC)reply
Hey Hawkeye7, thanks for the great article and for quick fixes! I support the nomination, and it's probably the best article about a spacecraft mission that I've read.
Artem.G (
talk) 06:40, 3 April 2024 (UTC)reply
T
I'm not going to do a review, I'd just like to repeat a comment from my
Good Article review three years ago that went unaddressed: the mission patch in the infobox is hideous, and it's not the real one. It's easy to find photos of the real one online
[11][12] and since it's NASA work it should be public domain.
Tercer (
talk) 08:50, 2 April 2024 (UTC)reply
NASA's statement regarding all of its missions emblems is:
Their reproduction in any form other than in news, information and education media is not authorized without approval.
Our use falls under this Fair Use clause, but Commons disagrees.
I am will to upload a non-free image if that is the consensus here.
Hawkeye7(discuss) 21:01, 2 April 2024 (UTC)reply
WSC
Queries by WereSpielChequers. I'm enjoying reading this but not sure I know enough about the topic to do a useful review.
"Galileo performed close observations of another asteroid, 243 Ida, at 16:52:04 UTC on August 28, 1993, at a range of 2,410 km (1,500 mi). Measurements were taken from Galileo" Was 2,410 the closest approach or the point where they started taking observations? Maybe I'm wrong but my understanding of these flybys is that there is a brief period of time to take observations, and observations start and end at a greater distance than the instance of closest approach.
I have elaborated on this. It was both the closest approach and the point where they started taking observations, due to an operational problem.
Hawkeye7(discuss) 20:25, 3 April 2024 (UTC)reply
"It orbits faster though, with a rotation period of 1.769 days. As a result, rotational and tidal forces are 220 times as great as those on Earth's moon." I thought that the greater mass and maybe proximity of Jupiter to Io as opposed to the Moon to Earth would explain the tidal forces. Though perhaps we are talking about tides on Jupiter as IO also faces Jupiter so the tidal forces would presumably be explained by a bulge.
Clarified that we are talking about Io.
Hawkeye7(discuss) 20:25, 3 April 2024 (UTC)reply
That's it for now, maybe more later ϢereSpielChequers 12:25, 3 April 2024 (UTC)reply
"The orbiter was powered by 570-Watt (at launch) radioisotope thermoelectric generators (RTGs)" how many of these 570 watt generators?
There were two of them; total output was 570 W.
Hawkeye7(discuss) 03:11, 9 April 2024 (UTC)reply
"The Rogers Commission handed down its report on June 6, 1986.[47] It was critical of NASA's safety protocols and risk management" I'm assuming this was a report on the Challenger disaster, but perhaps we should say so.
For now, just some random comments. I don't know if I'll have time for a full review.
Random comments are always most welcome.
Hawkeye7(discuss) 01:37, 7 April 2024 (UTC)reply
There's many citations to Meltzer 2007. Unfortunately, the PDF accessed by the URL only includes the front matter up to page xvii. Is there a better URL that gets the whole thing?
I had that problem too, but I thought it might be a issue with my browser. Switched to the 12 January archive.
Hawkeye7(discuss) 01:37, 7 April 2024 (UTC)reply
Background:
"They were followed by the more advanced Voyager 1 and Voyager 2 spacecraft, which were launched on 5 September and 20 August 1977 respectively" Is it worth a short explanation here of why Voyager 1 was launched after Voyager 2?
Probably not, but I have added a footnote explaining that Voyager 1 reached Jupiter and Saturn first.
Hawkeye7(discuss) 01:37, 7 April 2024 (UTC)reply
Initiation:
"NASA's Scientific Advisory Group (SAG)" the acronym SAG is never used after being defined here, so no reason to have it.
"a Mariner spacecraft like that used for Voyager". I'm not 100% sure what this means. I think you mean "as was used for Voyager". The way it's written now, I could be taken to mean "of similar design".
"This allowed it to take high resolution images". Clarify what "this" and "it" refer to. Either or both could be the accelerometer, which I don't think is what you intended. It's also unclear how better attitude control affected the camera resolution, which I assume was only a function of the camera sensor.
It is easier to take longer exposures images if the camera is held still.
Hawkeye7(discuss) 01:37, 7 April 2024 (UTC)reply
Sure, but less camera motion is not the same as higher resolution. On the other hand, now that I've got the full Meltzer PDF (thanks!), I see that it does indeed say "could help maximize photographic resolution". I think that's a bizarre way to say it, but that is what the source says, so who am I to argue with NASA?
RoySmith(talk) 02:22, 7 April 2024 (UTC)reply
"Independent Agencies Appropriations Subcommittee". Many of these subcommittees have a linkable article. Is there one for this?
"Casani solicited suggestions for a more inspirational name for the project". I had to go hunting a few paragraphs back to figure out who Casani was, so maybe re-introduce him here as "project manager Casani"?
"the Galileo project's engineers decided" I think you can just say "project engineers decided" and trust the reader to understand that you're talking about the Galileo project.
Changed as suggested
"To enhance reliability and reduce costs ... This improved reliability and reduced costs" eliminate the redundancy.
"Another 165 kilograms (364 lb) was added in structural changes to improve reliability" aerospace engineers don't take on 165 kg without a good reason (famous quote: "I’d sell my grandmother for a one-pound reduction!"); is there something more we can say here about what this additional weight was used for?
I've checked all three sources, and noine are specific on this point.
Hawkeye7(discuss) 03:01, 9 April 2024 (UTC)reply
"the three-stage IUS was itself overweight" overweight compared to what? It's maximum design capacity? Some assumed weight used in early mission calculations?
"NASA decided to split Galileo into two separate spacecraft, an atmospheric probe and a Jupiter orbiter". This is confusing. Perhaps this gets cleared up later on, but at this point I'm lost, trying to figure out if we're talking about one spacecraft or two. Here, you talk about two. But in the lead, you say "the Galileo spacecraft consisted of an orbiter and an entry probe. It was delivered into Earth orbit on October 18, 1989" so that's one spacecraft.
"a signal from Earth takes anything from 35 to 52 minutes to reach Jupiter". A few points here. First, "anything" is kind of informal language. But more importantly, I'd explain the nature of this variation; i.e. it's because the Earth-Jupiter distance varies depending on where they both are in their orbits; readers who are not familiar with how this stuff works might guess it has to do with other factors like varying amounts of power available on the spacecraft, or whatnot. Also, I think these sorts of things are typically cited as round-trip time because that's what really matters if you're trying to do remote control; downlink delay to send telemetry, plus the uplink delay to send a command based on the telemetry you received.
"autonomous spacecraft,[35] which was a necessity for deep space probes," There's something odd about the grammar here, but I'm not sure what. Maybe "were a necessity" (or, just "were necessary")?
As a generic comment, you use "flyby" many times in the article, but never explain what it is. For the benefit of our readers who don't know anything about spaceflight, you should explain what a flyby is the first time it's used in the main body.
Even more generically, please read through the entire article looking for technical words and consider whether a naive reader would understand them. As an example, you talk about "the orbiter in February 1984 with the probe following". How does an orbiter differ from a probe? Other words that might need explaining include "autonomous", "attitude" (we don't want to be launching any spacecraft in a bad mood!) but those are just a few examples, I'm sure you'll find more.
Still talking generically, it might be a good idea to give real-life examples of units that a reader might be unfamiliar with. For example, "a lithium–sulfur battery rated at 730 Watt-hours"; it would help the reader understand this better if you said that was about how much energy is in a typical car battery (but please double-check me on that and find a
WP:RS)
On average, a 12-Volt car battery can maintain about 5 Amperes for ten hours. That makes such a battery a 50 Ampere-Hour battery. That is equal to around 12 x 50 = 600 Watt-Hours. No idea if
this is a reliable source.
Hawkeye7(discuss) 19:21, 9 April 2024 (UTC)reply
(my apologies for these comments comming in dribs and drabs)
"general-purpose heat source radioisotope thermoelectric generators (GPHS-RTGs)"
WP:SEAOFBLUE. I suggest only linking to
GPHS-RTG, and let people drill down from there if they want more details.
"generated 570 Watts at launch ... rated at 730 Watt-hours." I'm not sure how to handle this better, but it's jarring to have two consecutive sentences talking about power sources using different units (power vs energy). I understand the difference, but I suspect a less technically savvy reader will just be confused and/or come away with the wrong impression that the battery is "bigger" than the RTG, when in fact those values can't be compared in any useful way. I see that you're just giving the data as it's presented in the NASA report, but it would still be nice if there was a better way to present this. Actually, a quick calculation says average of 520 watts x 8 year = 36 MW-Hrs. Upon reflection, this makes sense; the battery only runs the atmopheric probe for the short time it takes to descend and burn up. Hopefully you can find some RS that goes into this sort of analysis so you can present it in the article.
This still needs to be addressed.
RoySmith(talk) 22:38, 17 April 2024 (UTC)reply
"Heavy Ion Counter." Why the upper case?
A holdover from the original version, which used this form. After a change in the MOS (
MOS:EXPABBR) in 2017, I and other editors went through the article and removed the uppercasing of abbreviated forms. De-capped.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
Reconsideration
"flight tore the spacecraft apart" seems like an unencyclopedic way to phrase that. Maybe something like "Resulted in loss of the vehicle and the deaths of ..."
There was a debate about this in one Challenger disaster article. Some people wrote that the spacecraft exploded when it was actually torn apart by aerodynamic forces. This article follows the more precise wording chosen over there.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
"This was only partly due to the NASA management's increased aversion to risk in the wake of the Challenger disaster; NASA management also considered ..." This appears to be based on a p 217 quote from Marty Winkler of General Dynamics commenting on his interpretation of NASA management's decision. So I think this deserves attribution as Winkler's opinion.
Is is the opinion of historians Virginia Dawson and Mark Bowles.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
OK, so it needs some attribution, "According to Virginia Dawson and Mark Bowles ..."
RoySmith(talk) 22:40, 17 April 2024 (UTC)reply
"for a time it looked like its next trip would be to the Smithsonian Institution." That's a cute way to phrase it, but maybe it should be stated a bit more formally. Also, it's an unattributed quote from the source, so that's a problem.
Altered to match the quote, and turned into a quotation.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
"southerly declination of −23 degrees" -> "declination of 23 degrees south" Likewise for "northerly one of +18 degrees"
"Furthermore ... so the main tracking station would be the Canberra Deep Space Communication Complex in Australia". That makes it sound like using Canberra is a problem. Is it? Why?
Redundancy. There was only one complex in the southern hemisphere but two in the northern. Expanded on this.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
Nuclear concerns
"plutonium in the Galileo's radioisotope thermoelectric generators (RTGs) and General Purpose Heat Source (GPHS) modules" This makes it sound like these are two different things, each with their own plutonium supply. My reading of
GPHS-RTG leads me to believe this is a single unit with a single plutonium supply which performs both functions, so this needs to be clarified.
Correct. Changed to "Galileo's GPHS-RTG modules
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
The overall tone of the first paragraph seems in violation of
WP:NPOV. You minimize the risk ("what they perceived as an unacceptable risk") and then state in wiki-voice that "They had been used for years in planetary exploration without mishap", implying that there is indeed no risk.
There is a whole paragraph about the risk. The issue is what degree of risk is "unacceptable".
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
" If the Galileo/IUS combination fell free of the orbiter". Missing a word? of -> from, perhaps?
Looks okay to me, but changed "of" to "from"
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
Ugh. I must be becoming dyslexic. I read that as "free fell", as "the RTG was in free fall". My bad.
RoySmith(talk) 00:15, 14 April 2024 (UTC)reply
"an accident might have released up to 11,568 curies (428,000 GBq)." Another example of a unit which is almost certainly unfamiliar to most of our readers. Is that a lot? Are we talking a couple of dental X-ray's worth or another Chernobyl? Likewise with "NASA concluded that the chance of such a disaster was 1 in 2,500". I have no idea if that's a lot compared to all the other risks. NASA must have some standard risk analysis budget. How does this compare with other missions? Also, what does "such a disaster" refer to? In ther previous paragraph you give two different scenarios; which of those is this?
Chernobyl released between 50 and 185 million curies; three mile island released about 2.5 million curies. I have no figures on the risk assessments of other missions. Part of my job involves carrying out risk assessments, and the low odds and moderate consequences would mean approval. Linked the unite. Deleted "such".
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)+reply
Launch
"There were fears that the spacecraft might be hijacked by anti-nuclear activists or terrorists". I'm guessing this is due to the plutonium, but please don't make the reader guess. As an aside, I also have to wonder about the risk was of sleep-deprived truck drivers in a high speed convoy over an unfamiliar route at night having a crash. :-)
"three hours into the flyby, the tracking station at Goldstone had to be shut down due to high winds" If it was being tracked by Canberra and Madrid, why did it matter what was going on at Goldstone? I'm guessing the answer is that by the time three hours had passed, Goldstone had become the active station, but that should be explained for the benefit of our less technically savvy readers. It also seems odd that you give the time of the flyby down to the second ("05:58:48 UTC") implying it's a discrete moment in time, then later talk about being three hours into it. Maybe just note that 05:58:48 was the time of closest approach?
Clarified. Note that 10 February in Canberra and Madrid was only 9 February at JPL.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
Maybe I'm just missing it but I don't see where you explained this.
RoySmith(talk) 22:53, 17 April 2024 (UTC)reply
"Galileo's closest approach to Venus came at 05:58:48 UTC on February 10, 1990, at a range of 16,106 km (10,008 mi)."
Hawkeye7(discuss) 23:58, 17 April 2024 (UTC)reply
You might also want to explain that doppler provides a direct measurement of the relative velocity between two bodies (in this case, Galileo and the Earth). Again, this is something our more sophisticated readers will know, but will leave others struggling to understand.
Yeah, but I think it would still be better to provide some explanation here. I suspect most people are familiar with the "train whistle gets lower in pitch as the train passes" demonstration, but I don't think they would necessarily make the leap to "by measuring the change in carrier frequency of the spacecraft's transmission compared to the nominal frequency, you can compute the spacecraft's velocity relative to Earth", and
Doppler effect isn't much help for the casual reader trying to figure that out. Likewise, they might have heard of "Doppler radar" in the context of some gizmo the cops use to give you a speeding ticket, but I think it's asking a lot to expect the casual reader to understand the application of that to space navigation.
RoySmith(talk) 00:27, 14 April 2024 (UTC)reply
"Earth's strong magnetic field causes this to occur ... from its center," it's unclear what "this" and its" refer to. I think you're talking about the Earth's bow shock, and the Earth's center, but clarify.
"causes the bow wave", I assume "bow wave" and "bow shock" are synonyms, but perhaps reduce confusion by just using the same term in both places.
Used "bow shock" consistently.
Earth encounters
"Galileo made two small course corrections on 9 to 12 April and 11 to 12 May 1990". The source says, "TCM4 was the largest course correction that Galileo would have to perform", which seems at odds with your statement that they were "small".
"the first time that a deep space probe had returned to Earth from interplanetary space." this is almost word-for-word from the source and is thus a
WP:CLOP violation. Either rephrase in your own words or make it a direct quote.
"The opportunity was taken to conduct a series of experiments." This sentence only makes sense when read in the context of the section heading; it should stand on its own.
"another groundbreaking experiment was performed" in who's opinion was it groundbreaking? And since this is "another groundbreaking experiment", what were the other(s)?
Probably the sources, which are often written in American English. Deleted "groundbreaking".
Hawkeye7(discuss) 00:13, 14 April 2024 (UTC)reply
"at a wavelength of 532 nm" I'll admit to not understanding most of
Nonlinear optics, but I assume if the frequency doubled, the wavelength is halved, which leads me to wonder if 532 nm is the wavelength before or after the frequency doubling.
"Cassegrain telescope" link to
Cassegrain reflector (I assume that's the right target). I've never heard of using a telescope to transmit an optical beam, but obviously the optics are symmetric, so I assume you put the laser into "eye" end, but it might be worth clarifying that.
The source says: "coupled to a Cassegrain telescope through a coudé mount arrangement."
Hawkeye7(discuss) 00:13, 14 April 2024 (UTC)reply
"produced images of Earth clearly showing the laser pulses" did they just detect the pulses, or was data actually communicated over this carrier?
Just detected. The article goes on to describe subsequent work on laser communications.
Hawkeye7(discuss) 00:13, 14 April 2024 (UTC)reply
High gain antenna problem
"Once Galileo headed beyond Earth, it was no longer risky to employ the HGA", HGA was defined several sections earlier; it might be useful to re-introduce where what the acronym means.
"They would drive a worm gear." Not clear what "they" is; probably "the actuator motors", but this and the previous sentence could be combined and rephrased to make that more clear.
"the spacecraft's spin rate had decreased" I assume this was due to the increased moment of rotational inertia? If so, it would be good to explain that (assuming a RS says so).
"so after five deploy and stow operations, the DDA torque was half its original value" This is confusing. Previously you said they didn't try to refold it, and now you're saying they tried five times. Something's amiss here.
Nothing is amiss; they did not try to refold it. Deleted the (correct and sourced) sentence to remove any confusion.
Hawkeye7(discuss) 00:13, 14 April 2024 (UTC)reply
"during the 4.5 years that Galileo spent in storage ... eroded and worn by vibration during the three cross-country journeys by truck" So, did the damage happen during storage or during truck rides?
"since it transmitted a signal isotropically" this is confusing. Earlier you talk about swinging LGA-1 and LGA-2 to their hard stops, which implies some kind of aiming capability. But now you're talking about isotropic radiation, which to me says it's not aimed in any particular direction. This should be clarified.
Looks like you have found an error in the source. Corrected.
Hawkeye7(discuss) 00:13, 14 April 2024 (UTC)reply
I don't understand what "which transmitted over a one-sixth half-angle" means. One-sixth of a degree? One sixth of the beamwidth of the LGA? Also, in "its bandwidth was significantly less", I'd be specific and say "data bandwidth" or "digital bandwidth", or even better, "data rate" to avoid confusion with
Bandwidth (signal processing).
RoySmith(talk) 14:39, 14 April 2024 (UTC)reply
Also, "The two LGAa were capable of ... but since it transmitted its signal" plural/singular inconsistency.
RoySmith(talk) 14:40, 14 April 2024 (UTC)reply
And, "but since it transmitted its signal over a cone with a 120-degree half-angle ... its bandwidth was significantly less than that of the HGA," implies that the beamwidth was the only cause of the reduced data rate. In reality other causes were reduced transmit power and (if I'm reading this right) the need to use a smaller aperture receiving antenna on S-band.
RoySmith(talk) 14:45, 14 April 2024 (UTC)reply
Typo. It should have been "a half-angle of one-sixth of a degree". Corrected.
Hawkeye7(discuss) 21:57, 14 April 2024 (UTC)reply
You also should say some more about how they switched to a better compression algorithm. The JPL source says "By programming a software (11,1/2) convolutional code on a Galileo compute". I assume this meant they had the ability to upload new software to the spacecraft, which certainly deserves at least some explanation.
RoySmith(talk) 14:50, 14 April 2024 (UTC)reply
Yes, they had the ability to send software updates.
Hawkeye7(discuss) 21:57, 14 April 2024 (UTC)reply
Added a bit about the compression algorithms used.
Hawkeye7(discuss) 05:14, 15 April 2024 (UTC)reply
"Conservatism was not restricted to engineers ... putting a wooden ruler up to the screen." This sentence seems out of place for this section.
Storage was expensive in the 1980s. The organization I worked for abandoned plans to put five years data online in favour of just 12 months because each month required a disk that cost $20,000 at the time, so that saved nearly a million dollars. A decade later, I bought the 48 disks for $200 each on my corporate Amex card.
Hawkeye7(discuss) 21:57, 14 April 2024 (UTC)reply
"Perhaps the most surprising feature was several relatively flat planar areas" Who is making the editorial judgement about how surprising this is? "According to Joe Scientist, the most surprising feature was..."
"Galileo suddenly abandoned the program and resumed its cruise configuration." Unclear what that means. What is "the program"? Does resuming it's cruise configuration mean it attempted to undo the course correction, or powered down the instruments it was going to use for observing, or something else maybe? Also, "suddenly" sounds like editorializing, so attribute: "Fred Flight Controller said the configuration change happened suddenly".
"Measurements were taken from Galileo using SSI and NIMS" Drop "from Galileo". Of course they were taken from Galileo; there's no other possible place they could have been taken from.
"The requirement to use the LGA resulted in a transmission rate of 40 bits per second." You've said this already in a previous subsection, so no need to repeat. Or maybe something like: "At this time, the LGA was still only running at the 40 bps data rate available during the Gaspra flyby", which gives the reader some context about where they were in the ongoing efforts to increase the data rate.
"A tiny Doppler shift in the signal of the order of a few centimeters per second" This seems like a weird mixing of units. Doppler shift is a change in frequency. From that you can compute a velocity. So, "A velocity change of a few centimeters per second, as measured by Doppler shift".
"it was fired for the first time" Perhaps I'm picking nits here, but was it ever test fired on Earth? If so, "fired for the first time in XX years", or "after completing its manufacturing tests", or whatever. It's certainly possible this was its first firing ever; some engines are never test fired before a mission, but some are.
"The main engine could not be tested or fired prior to release of the atmospheric probe because the probe was mounted in front of the engine nozzle."
Hawkeye7(discuss) 21:57, 14 April 2024 (UTC)reply
"it would perform as a communications relay": maybe "perform" -> "act" ?
" The Galileo probe's project manager ... this role could be performed by LGA-1" This sentence is awkwardly placed. The previous sentence talks about firing the engine, and the next sentence talks about how that firing changed the velocity, but this sentence has nothing to do with the engine.
The engine was fired to place the orbiter in a position to act as a relay for the probe.
Hawkeye7(discuss) 21:57, 14 April 2024 (UTC)reply
The "Isbel, Douglas; Wilson, James H. "Galileo Flying Through Intense Dust Storm" (Press release). NASA/Jet Propulsion Laboratory. 95-147. Retrieved November 16, 2020. URL can't be reached.
"The bow shock was not stationary, but moved to and fro in responses to solar wind gusts" "not stationary" is redundant with "moved". Also, responses -> response
" Most robotic spacecraft respond to failures by entering safe mode ... not possible for Galileo.[136]" You've already discussed the need for autonomous operation in Preparation; no need to go over that again here.
"The descent probe awoke in response to an alarm" the word "alarm" sounds like there was some kind of failure that it was responding to. Maybe "timer" wou;d be a better word?
"Alarm" is more technically correct. In computing, an alarm is for a clock time, whereas a timer is relative to the CPU cycles.
Hawkeye7(discuss) 20:32, 15 April 2024 (UTC)reply
"encountered a previously undiscovered belt of radiation ... Before the atmospheric entry, the probe detected a previously unknown radiation belt". Is this two different belts? Needs to be clarified one way or the other.
There is only one; the sources confused the article writer.
Hawkeye7(discuss) 20:32, 15 April 2024 (UTC)reply
You use "bars" as a unit. I'm pretty sure it's not supposed to be pluralized, i.e. "1.5 to 2 bar". I also don't see the point of {{convert}} here; that's useful for metric-english conversions, but bar -> kPa doesn't add anything of value.
"bars" is correct. Surprised that it converted to kilopascals; removed the conversion as unecessary.
Hawkeye7(discuss) 20:32, 15 April 2024 (UTC)reply
"The probe slowed to subsonic speed" It's not clear what "subsonic" means in this context. I assume we're talking about below the speed of sound in the local Jovian atmosphere? If so, clarify that, and give a number for what Mach 1 is in those conditions.
Checking the sources, I find that Mach 50 is 170,000 kph, which we already said. I find Mach confusing in this context myself, although it is sourced, so removed.
Hawkeye7(discuss) 20:32, 15 April 2024 (UTC)reply
"which would then take days to arrive using the LGA" maybe "to be transmitted" instead of "to arrive"?
"it entered a 198-day parking orbit" link
Parking orbit. Also, it's not clear what 198 days refers to. Is that how long it was in orbit, or how long a single orbit took?
" Only the fields and particles instruments were allowed to collect data, as these required the tape recorder to run at slow speeds, and it was believed that it could handle this, whereas the SSI camera required it to operate a high speed, with abrupt stops and starts." This is almost word-for-word from the source. See
WP:CLOP.
"When Galileo next approached Io on I25 at 20:40 Pacific Time" I get that the source you're citing uses Pacific Time, but you're using UTC everywhere else, so convert to UTC.
"Galileo flew past Io on arrival day" explain what "arrival day" is, probably under the "Arrival" section above. There's a bunch of possible days that could be called that (arrival at the bow shock, closest point of approach to Jupiter, entering orbit, etc)
"As a consequence, three quarters of the observations were taken over a period of just three hours." I don't understand why this is a consequence of there being an Earth-Sun conjunction.
Galileo cannot be received when the line of sight is blocked.
Hawkeye7(discuss) 04:49, 16 April 2024 (UTC)reply
Yeah, but that only affects transmitting data to Earth. Observations can still happen and record the data on tape, so I still don't see how one is a consequence of the other.
RoySmith(talk) 17:47, 16 April 2024 (UTC)reply
"The I24, I25 and I27 encounters had been on equatorial orbits, which made it difficult to determine whether Io had its own magnetic field, or one induced by Jupiter" why does being in equitorial orbit make this difficult? And, are we talking about Jupiter's equator or Io's equator?
Source says: "All of our previous magnetic measurements at Io have been on equatorial passes, and from those we can't tell whether the field at Io is induced by Jupiter's strong magnetic field or produced by Io itself". No idea why.
Hawkeye7(discuss) 04:49, 16 April 2024 (UTC)reply
"but data transmission was hindered by a Solar occultation" link to
Occultation
"with a diameter of 5,270 kilometres" you describe the other moons by their radii. Pick one and use it consistently. Also, be consistent about kilometres vs kilometers.
"strength of about 750 nanoteslas (0.0075 G)" Tesla and Gauss are both SI units; no need to show both. But it would be useful to compare this to the strength of Earth's magnetic field, since most readers will have no clue how big a Tesla is.
"This discovery led naturally to questions about its origin." "This" and "its" both refer back to the previous paragraph. Maybe just combine the two paragraphs.
"enabling a higher bit rate despite the spacecraft's long distance from Earth", Drop the "despite ...." clause; the larger aperture allowed for a higher bit rate regardless of all other factors. The biggest problem here was that the HGA was inoperative; the transmission distance was exactly what was expected during mission planning.
"predominantly >2 MeV (0.32 pJ) electrons" Is there any reason to convert to J? I would think MeV would be the universally used unit of measurement here.
They are, but...
MOS:CONVERSIONS: "For units of measure that are ... not part of the SI or US customary systems... supply a parenthetical conversion into at least SI units." Electron volts are
Non-SI units mentioned in the SI, hence a conversion is supplied.
Hawkeye7(discuss) 20:13, 16 April 2024 (UTC)reply
"Galileo impacted Jupiter in darkness just south of the equator" What does it mean to "impact" something made of gas?
The sources consistent use the term, and we have a whole article on
impact events on Jupiter that does not define it. But at some point it gets so dense that it is like hitting a solid surface.
The astronomers inform me that this is the case on Earth too; "impact" is 50-80 km up, not on the surface.
Hawkeye7(discuss) 05:22, 6 May 2024 (UTC)reply
"Galileo had not been sterilized prior to launch and could have carried bacteria from Earth." link sterilized and bacteria.
OK, finally got to the end. So much for "just some random comments" :-) I'm going to give this a rest for a bit then come back and see how things look overall.
Second pass
The orbiter would be in orbit around Jupiter when the probe arrived, allowing it to perform its role as a relay." It's unclear what "it" refers to: the orbiter or the probe.
I thought it was clear enough, but changed it to "the orbiter".
Hawkeye7(discuss) 00:25, 18 April 2024 (UTC)reply
"required a second Space Shuttle mission and a second carrier to be built for the probe" What is the carrier? I'm guessing it's some mounting adapter that lets you install the probe into the shuttle cargo bay, but clarify.
No, it is a spacecraft. The probe wasn't intended to fly to Jupiter by itself. Clarified this.
Hawkeye7(discuss) 00:25, 18 April 2024 (UTC)reply
"NASA hoped to be able to recoup some of this through competitive bidding." You put that in just for comic relief, right?
The source says ""Delaying to 1984 is more cost efficient because we can go into more competitive bidding for the carrier."
Hawkeye7(discuss) 00:25, 18 April 2024 (UTC)reply
"President pro tempore of the Senate" I don't think I've ever seen this spelled out in full, it's always just "president pro tem", so that's probably what we should use here.
At this point, the lack of ALT text is the only thing holding me back from supporting this.
RoySmith(talk) 12:07, 19 April 2024 (UTC)reply
The ALT for
File:Galileo atmospheric probe.jpg got cut off (I assume there should be a number at the end), but that won't keep me from supporting. Overall, an interesting article. Thank you for submitting it, and for putting up with my nit-picking.
RoySmith(talk) 17:19, 25 April 2024 (UTC)reply
Sorry, meant "non-direct" link. As in, a link to the webpage where you found the image, not a link to the image itself. Such direct links can be hard to repair when they break, and the information the link is there for (e.g copyright statements) isn't on the file page.
Jo-Jo Eumerus (
talk) 08:20, 26 April 2024 (UTC)reply
A link has been added to the page where I found the image.
Hawkeye7(discuss) 15:12, 26 April 2024 (UTC)reply
Source review-wise, I am checking
this version; spot-check upon request. #44, #71, #75, #150, #175, #204 are broken. #177 can probably get a better source information than a raw URL. What makes #224 and #225 a reliable source? I am wondering about spaceflightnow.com too, since they don't give much information on themselves. I presume the differences between various sources with respect to identifiers are b/c some of them have identifiers and others don't? That needs doublechecking as e.g Cowen 2001 doesn't have the doi 10.2307/3981750 shown.
Jo-Jo Eumerus (
talk) 13:01, 25 April 2024 (UTC)reply
#44, #71, #75, #150, #175, #204 have the archive URL added.
Hmm? The only mention of Spaceflightnow.com is when it is compared to a different source.
Jo-Jo Eumerus (
talk) 08:20, 26 April 2024 (UTC)reply
I consider Spaceflightnow.com a reliable source for Spaceflight news. We can ask at the
WP:RSN.
Hawkeye7(discuss) 12:47, 26 April 2024 (UTC)reply
It's not clear to me what editorial oversight Spaceflight Now provides, and that's what determines if it's a RS or not. They have a "Member Content" section (
https://spaceflightnow.com/category/members/); I'd be wary of using anything from there (not that you have). Looking at the four citations to Spaceflight Now, two ("Galileo to fly over source of recent polar eruption on Io" and "Galileo data recorder still not working") are NASA/JPL NEWS RELEASE, so clearly no problem with those as far as RS goes, but the citations are wonky; they should have NASA/JPL as the publisher and Spaceflight Now noted as the content deliverer using the "via" attribute (or find the originals on a NASA site). "Galileo spacecraft crashes into Jupiter" is by Peter Bond who has published several books through reputable publishers (
https://peterbondspace.com/) so I'm inclined to accept him as a RS based on
WP:EXPERTSPS. "The Galileo trials" by Ben Evans I'm less sure about. He's described as "a schoolteacher and freelance astronomy and space exploration writer", so I'll need some more convincing to accept him as an expert.
RoySmith(talk) 16:42, 27 April 2024 (UTC)reply
I have replaced the two press releases with links to the associated NASA/JPL press release pages and removed the Ben Evans reference.
Hawkeye7(discuss) 02:03, 28 April 2024 (UTC)reply
Now that it's added, yes. I just wonder if there are other sources that could have DOIs added.
Jo-Jo Eumerus (
talk) 08:20, 26 April 2024 (UTC)reply
I added the doi in December 2020 (
[14]). Are we talking about the same link? Usually I rely on the citation bot to add them.
Hawkeye7(discuss) 12:47, 26 April 2024 (UTC)reply
Nevermind that, I have no idea what I was seeing there.
Jo-Jo Eumerus (
talk) 13:57, 26 April 2024 (UTC)reply
Hi
Jo-Jo, are we good on either or both of those reviews? Cheers.
Gog the Mild (
talk) 14:26, 14 May 2024 (UTC)reply
"Ames and JPL decided to use a Mariner spacecraft as was used for Voyager for the Jupiter orbiter...": Wouldn't "Ames and JPL decided to use a Mariner spacecraft also used in the Voyager for the Jupiter orbiter" be more clarifying and less confusing?
"In December 1984 Casani proposed adding a flyby of asteroid 29 Amphitrite to the Galileo mission. In plotting a course to Jupiter, the engineers were concerned to avoid asteroids": Consider rewording to "In December 1984, Casani proposed adding a flyby of the asteroid 29 Amphitrite to the Galileo mission. In plotting a course to Jupiter, the engineers were concerned about avoiding asteroids."
That would be ambiguous. Changed to: "In plotting a course to Jupiter, the engineers wanted to avoid asteroids."
Hawkeye7(discuss) 20:24, 22 May 2024 (UTC)reply
"the lightning activity: Consider removing the "the" prefix?
I'm not sure about this, but consider linking to high energy particles, heavy ions, and multispectral imaging so readers can have an idea of what these are?
In quite a few places, proper article prefixes are not there, I have noted down some of these here. Would it be ok with you if I made these minor edits myself?
Happy to extend my support for promotion to FA. Cheers
Matarisvan (
talk) 18:43, 25 May 2024 (UTC)reply
Overall, a very good article, sources are great.
Drive-by comments
Cites 72 and 73 should be pp, not p; and have en dashes, not hyphens.
Not page ranges; these pages are numbered with hyphens.
Hawkeye7(discuss) 19:11, 4 June 2024 (UTC)reply
No publisher location for Harland or National Research Council; European Space Science Committee (1998)?
Gog the Mild (
talk) 10:53, 31 May 2024 (UTC)reply
Closing note: This
candidate has been promoted, but there may be a delay in bot processing of the close. Please see
WP:FAC/ar, and leave the {{featured article candidates}} template in place on the talk page until the
bot goes through.
Gog the Mild (
talk) 19:21, 4 June 2024 (UTC)reply
The above discussion is preserved as an archive. Please do not modify it. No further edits should be made to this page.
This article is about a robotic space mission to Jupiter. This article is about the mission; there is a separate article about the spacecraft itself.
Hawkeye7(discuss) 20:59, 31 March 2024 (UTC)reply
UC
Very much coming in as a non-expert here, but it looks like a cracking article and at least gives me the illusion that I can understand what is going on. UndercoverClassicistT·
C 18:29, 1 April 2024 (UTC)reply
gravitational assist flybys: should this be gravitationally assisted flybys, as the first two words modify the third? I see no hits on Google Books for this precise phrasing.
It seems that "gravity assist flyby" is the correct scientific term
[2], so standardised on that.
Hawkeye7(discuss) 19:57, 1 April 2024 (UTC)reply
It launched the first probe into Jupiter: suggest The spacecraft launched to clarify that "it" isn't strictly the programme.
Jupiter's atmospheric composition and ammonia clouds were recorded. Io's volcanism and plasma interactions with Jupiter's atmosphere were also recorded: any way to avoid the slightly clunky repetition of were recorded?
Suggest linking "encounter", as it has a more specific meaning in this context than its everyday loose one.
Added a link to the Wiktionary entry (which I just created): "The period of a space mission during which it carries out its data-gathering objectives".
There was also concern about the effects of radiation on spacecraft components, which would be better understood after Pioneer 10 and Pioneer 11 had conducted their flybys. These indicated that the effects were less severe than feared: the tenses are a bit confusing here. How much time has passed between the two sentences? I'd suggest something in the middle to the effect of "these took place on [date] and indicated..."
who had headed the Mariner and Voyager projects: I'm not clear on the logic as to when names like Mariner and Voyager are italicised, but it seems to be inconsistent in this paragraph.
Longer travel times meant that components would age: well, yes, but I suppose the problem was that they would wear out with age? Things simply becoming older isn't necessarily a problem.
the onboard power supply and propellant would be depleted: is this quite true? For the first part, perhaps, but wasn't the point of the gravity assists that the overall mission would require less delta-v (and so less propellant) than a mission that didn't use them?
The onboard propellant is only used for inflight maneuvers, so gravity assist maneuvers would require more of them.
Hawkeye7(discuss) 18:48, 3 April 2024 (UTC)reply
Some of the gravity assist options also meant flying closer to the Sun, which would induce thermal stresses. However, the IUS was constructed in a modular fashion, with two stages: I'm not sure I see the point of the however here -- what's being contrasted? It sounds like we've just discussed reasons why the IUS was a bad component for this mission, and are now about to discuss reasons why it was a good one: could that be made clearer and more explicit?
Reworded the paragraph, and got rid of the "however".
Hawkeye7(discuss) 18:48, 3 April 2024 (UTC)reply
An important decision made at this time by Ames and the JPL was: a bit mealy-mouthed: better as Ames and the JPL decided...? Always better to show, not tell, that it was important, and we don't (in this paragraph at least) really set out why this made a difference.
The paragraph does explain: This allowed it to take high resolution images, but the functionality came at the cost of increased weight.Hawkeye7(discuss) 18:48, 3 April 2024 (UTC)reply
In which case, as we've shown,
WP:PUFFERY et al would encourage us not to use the word important, but rather to let the facts speak for themselves. UndercoverClassicistT·
C 19:51, 3 April 2024 (UTC)reply
The IUS was not powerful enough to launch a payload to Jupiter without resorting to using a series of gravity assist maneuvers around planets to garner additional speed: could we rework the double negative: something like "to launch a payload to Jupiter, the IUS needed to use a series of..."? I would also stick a full stop after additional speed and then do something like "Most engineers regarded the use of such maneuvers as..."
The second, but not the first. I'm not sure what the "otherwise" at the start of the new sentence means: was there any scenario in which the IUS would be powerful enough to avoid using gravity assists? UndercoverClassicistT·
C 21:07, 3 April 2024 (UTC)reply
A three-stage might have worked; "otherwise" refers to the two-stage IUS. I thought this was clear enough, but emphasised.
Hawkeye7(discuss) 03:18, 4 April 2024 (UTC)reply
Casani solicited suggestions for a more inspirational name for the project, and the most votes went to "Galileo" after Galileo Galilei: in both cases, I find myself asking: [suggestions/votes] from whom?
a launch on Space Shuttle Columbia on STS-23 : the Space Shuttle (like the battleship New Jersey) -- unless this is the HQRS norm? I'd also clarify something like "the STS-23 mission".
Lifting Galileo and the IUS would require: in this and similar sentences, if they actually did the thing suggested, it's better in the indicative: Lifting G. and the IUS required....
As explained further on, they did not do it.
Hawkeye7(discuss) 04:12, 4 April 2024 (UTC)reply
By late 1980, the price tag for the IUS had risen to $506 million (equivalent to $1.714 billion in 2023). The USAF could absorb this cost overrun: I'm not totally clear on the relationship between NASA and the USAF in this project. Had NASA contracted the Air Force?
As explained earlier, the USAF was in change of the two-stage IUS, NASA of the three-stage one.
What saved it from cancellation was the intervention of the USAF: less verbose as the USAF intervened to save it from cancellation.
I fail to see the value, but changed as suggested.
Hawkeye7(discuss) 04:12, 4 April 2024 (UTC)reply
in reality, the antenna got stuck while in space and didn't open all the way: I know that brevity is important in a caption, but I don't think "got stuck" or a contraction are the right
WP:TONE. Suggest "the antenna's motors stalled, preventing it from fully opening", or similar. UndercoverClassicistT·
C 10:27, 3 April 2024 (UTC)reply
The problem was not with the motors, but with the antenna being stuck, probably vacuum welded in place. Re-worded to address the issue.
Hawkeye7(discuss) 18:48, 3 April 2024 (UTC)reply
Not sure about the revised but in reality the antenna could not open all the way: to me, that reads as if it was impossible for the antenna to open fully. UndercoverClassicistT·
C 21:07, 3 April 2024 (UTC)reply
Simplified the caption to "the antenna could not extend"
Hawkeye7(discuss) 03:18, 4 April 2024 (UTC)reply
I still think we have the same problem: it sounds as though the antenna wasn't extendable at all. How about "failed to extend", which makes clear that it should have done so? UndercoverClassicistT·
C 06:20, 16 April 2024 (UTC)reply
pressurized atmospheric entry probe to a vented one: it would be useful to know what these things are: perhaps clearer if we explain it by what the probe would or wouldn't do?
But the three-stage IUS was itself overweight: It's not a rule, as such, but most style guides would avoid starting a sentence with but. More importantly, if we do use but here, we're setting up some followup in which this additional weight prevented something from taking place, and that never comes, so the paragraph would read better with something like "Furthermore", "Additionally", or indeed nothing at all.
After digging through various technical documents, I have added a footnote: "The rated power level (RPL) is the power at which an engine can be normally operated. In the case of the Space Shuttle, the specification called for 27,000 seconds operation at 100 percent of the RPL, or 14,000 seconds at 109 percent of the RPL, which was designated full power level (FPL)."
Hawkeye7(discuss) 04:17, 21 April 2024 (UTC)reply
The second was that despite this, it was also more gentle than the IUS, as it had lower thrust, thereby minimizing the chance of damage to the payload.: grammatically, needs a comma before despite this, but then becomes quite a winding sentence. I would go with something like The second was that it had lower thrust, thereby minimizing the resultant forces on and therefore the chance of damage to the payload.
could damage the spacecraft's optics and possibly the spacecraft itself.: the optics are part of the spacecraft, aren't they? Suggest "and possibly other parts of the spacecraft", or even something like "other, more mission-critical parts of the spacecraft", "other parts of the spacecraft, particularly..."
reads from one memory location disturbed those in adjacent locations: not quite grammatical (what's the antecedent of those: grammatically, it should be reads, but you can't damage a read). The noun "reads" is also a little tricky to parse. Suggest "repeatedly reading data from a single data cell damaged the other data cells around it", or similar.
That's not the case here, though, as there's nothing called a "Shuttle-Centaur" (that is, a Centaur that is also a shuttle, as distinct from maybe a "Saucer-Centaur"). This is instead the example given of Wilkes-Barre, a single city named after two people, but Minneapolis–Saint Paul, an area encompassing two citiesUndercoverClassicistT·
C 08:38, 16 April 2024 (UTC)reply
We used a hyphen in the featured article, and it is used in the sources. The form with a solidus is also used in the sources.
Hawkeye7(discuss) 11:07, 25 April 2024 (UTC)reply
Reading around, I can see the case for a hyphen: happy with this. UndercoverClassicistT·
C 14:37, 25 April 2024 (UTC)reply
Had been holding off while Roy concluded his review: thanks for the nudge. More below. UndercoverClassicistT·
C 16:02, 14 May 2024 (UTC)reply
The section on Nuclear concerns seems very determined that there was no real reason why anyone should have been worried about the plutonium. Is this the consensus of the sources?
Yes, but the sources are written by experts, who tend to have much less fear of radioactive substances than the general public.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
That's a fair point. Still, there are plenty of experts who have criticised the safety elements of other early-ish space missions and nuclear projects, so if none of them have really challenged the NASA narrative, I think
WP:DUEWEIGHT is satisfied. UndercoverClassicistT·
C 10:53, 15 May 2024 (UTC)reply
NASA concluded that the chance of a disaster was 1 in 2,500, although anti-nuclear groups thought it might be as high as 1 in 430. The risk to an individual would be 1 in 100 million, about two orders of magnitude less than the danger of being killed by lightning.: the first bit of this attributes both figures, recognising that there's a possible debate here, but the second doesn't: it's cited to NASA, however, who certainly had a horse in this race, so I don't think we can present it as straightforward, disinterested fact. If nothing else, the figure here surely depends on the overall probability of a disaster?
Changed to reiterate that this was NASA's opinion.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
This created a novel mission failure modality that might plausibly have entailed dispersal of Galileo's plutonium : could this be re-written in plainer English?
The risk to an individual would be 1 in 100 million, about two orders of magnitude less than the danger of being killed by lightning. The prospect of an inadvertent re-entry into the atmosphere during the VEEGA maneuvers was reckoned at less than one in two million: consistency advised under
MOS:NUM
an accident might have released up to 11,568 curies : not a common unit of measurement: can we contextualise that a bit? Would that be bad?
There is a link. The Three Mile Island accident released 2.5 million curies. Added a bit more from the risk assessment.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
There are some hyphens in page ranges in the footnotes (I noticed on note 74).
These are not page ranges. Hyphens are okay.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
Note 73 is Office of Space Science and Applications 1989, p. 2-24.. That's a page range, surely? Ditto 72: Office of Space Science and Applications 1989, p. 2-23.. We also generally use pp. or pages for a range. If p. stands for something other than "page", I think that would be wise to clarify (e.g. "section P" or similar). UndercoverClassicistT·
C 06:29, 15 May 2024 (UTC)reply
The document uses a page numbering system where pages have numbers like 2-4 and 4-18. In the text, this is documented by using the form p. 2{{hyphen}}4.
Hawkeye7(discuss) 19:41, 15 May 2024 (UTC)reply
Ah, gotcha. Happy here, then: it looks wrong (and might lead to well-meaning editors like myself trying to change it), but it's correct. You could perhaps use the |at= parameter rather than |p=, which would drop the "p." -- as e.g. 2-23 is really sort-of an abbreviation for "part 2, page 23"? UndercoverClassicistT·
C 20:48, 15 May 2024 (UTC)reply
There were fears that the spacecraft might be hijacked : presumably they would hijack the trucks, rather than the spacecraft, as the latter wouldn't be very easy to drive.
the appeal was therefore denied on technical grounds: is that technical grounds? It sounds like they denied it on substantive grounds: technical, to me, means that the proper procedures had not been followed, and so the issue was not considered, whereas the court did consider the issues but, as most appeals do, only had to determine that the original decision had been made legally and reasonably, not that it had been correct.
The source says: "The rejection of the appeal, by the D.C. Circuit Court of Appeals, was based on technical grounds and was not a ruling on the merits of the case."
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
In that case, we've got a contradiction here. If the reason for rejection was, as we've said, Chief Justice Patricia Wald wrote that while the legal challenge was not frivolous, there was no evidence that NASA had acted improperly in compiling the mission's environmental assessment (emphasis mine), that is a ruling on the merits of the case (that they weren't sufficient). Is this all from the same source: could you perhaps quote a bit more to see if we can see what's happened here? UndercoverClassicistT·
C 06:27, 15 May 2024 (UTC)reply
Re-worded to make it clearer that this was in the concurring opinion.
Hawkeye7(discuss) 19:41, 15 May 2024 (UTC)reply
343 kilometers (213 mi) orbit: singular and hyphenate (cf. a two-mile queue, a five-dollar note and a four-mile run).
Galileo's closest approach to Venus came at 05:58:48 UTC on February 10, 1990, at a range of 16,106 km: some inconsistency in the article about whether units are abbreviated or not.
Not per
MOS:HYPHEN: [hyphens are used] ... to link related terms in compound modifiers ... hyphens can aid ease of reading (that is, they can be ease-of-reading aids) and are particularly useful in long noun phrases: gas-phase reaction dynamics.UndercoverClassicistT·
C 11:12, 15 May 2024 (UTC)reply
As the spacecraft moved further from Earth, it also necessitated the use of the DSN's 70-meter dishes: not quite grammatical (the antecedent of it is the spacecraft, but the spacecraft didn't necessitate the use of the dishes: its movement did). Secondly, who were the other users of the dishes?
Not to me, I'm afraid, and it needs to be clear to readers who don't know much about astronomy, telemetry, and don't have an expert grasp of English. UndercoverClassicistT·
C 11:12, 15 May 2024 (UTC)reply
Earth's magnetic field causes the bow shock to occur at around 65,000 kilometers (40,000 mi) from its center, but Venus's weak one: weak magnetic field, or weak centre?
Magnetic field. Added, although it makes the text harder to understand.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
If you want it clearer, how about but Venus's magnetic field is weaker, causing the bow shock to occur nearly on the surface? UndercoverClassicistT·
C 06:31, 15 May 2024 (UTC)reply
plasma wave detector: hyphenate as a compound modifier.
It's not a proper noun: we're using the term for a thing that detects plasma waves. If we want to refer to a specific thing by the name of "plasma-wave detector", and so to make it a proper noun, we would need to capitalise, but we don't do that for other unique parts of a ship: the thrusters, the engines, the wings and so on are all lower-case. Sources may not hyphenate, but they may have their own house style, and don't have to follow the MoS: we do. UndercoverClassicistT·
C 11:09, 15 May 2024 (UTC)reply
Changed. But I am not changing it elsewhere.
Hawkeye7(discuss) 19:41, 15 May 2024 (UTC)reply
on 9 to 12 April and 11 to 12 May 1990: the prevailing style here seems to be MDY, so I'd switch to that.
Yes, it uses mdy. God knows why, as all the sources use the normal format.
Hawkeye7(discuss) 20:41, 14 May 2024 (UTC)reply
This was only 8 kilometers (5 mi) higher than predicted, and the time of the closest approach was only a second off.: I would cut both onlys as editorialising, possibly rephrasing slightly to e.g. "the time of the closest approach was within a second of what had been predicted".
That's up to the start of "Earth encounters": will be back once you've had a chance to look at this batch. I appreciate it's a lot: it's a big article that is saying a great deal and doing an admirable job of getting the nitty-gritty across while keeping it clear and engaging. UndercoverClassicistT·
C 16:02, 14 May 2024 (UTC)reply
Marching on:
energetic particles detector: you can probably guess this one: hyphenate (particularly useful here: it was the particles, not the detector, that were energetic).
by 35 meters per second: should we include an imperial conversion here (mph/fps) as we have for most other measurements?
Added. The purpose of the conversions is to render historic measurements in the sources into metric. Converting metric to imperial serves no purpose other than looking consistent.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
at a range of 960 km (600 mi) at 20:34:34 UTC on December 8, 1990. This was 8 kilometers (5 mi): there are other examples, but I'd advise consistency as to whether units are abbreviated or not (generally, per
WP:NOTPAPER, I'd suggest not, but there's an argument for not writing out "kilometers" in full if the word is coming up several times in a sentence or paragraph).
MOS:UNITNAMES: "In prose, unit names should be given in full if used only a few times, but symbols may be used when a unit (especially one with a long name) is used repeatedly, after spelling out the first use". Abbreviated.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
Normally they are only seen in September or October, but Galileo was able to detect them in December, an indication of damage to Earth's ozone layer: is it possible to explain this a little, perhaps in a footnote -- what does ozone layer damage have to do with these things appearing earlier?
Just another experiment taking advantage of an instrumented spacecraft having an encounter with Earth.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
I'm not following: what I'm asking for here is an explanation of how an indication of damage to Earth's ozone layer follows from Normally they are only seen in September or October, but Galileo was able to detect them in December. It's clear enough that this was an abnormal observation, but not clear how it indicated damage to the ozone layer. UndercoverClassicistT·
C 06:30, 21 May 2024 (UTC)reply
I'm not an atmospheric physicist, but added a one-sentence explanation.
Hawkeye7(discuss) 07:17, 21 May 2024 (UTC)reply
As I read it, it sounds as though these clouds would cause the damage, rather than being a sign or consequence of it: could we make that a bit clearer, if so?
The text says: "The NIMS was employed to look for
mesospheric clouds, which were thought to be caused by
methane released by industrial processes. The water vapor in the clouds breaks down the
ozone in the upper atmosphere. Normally the clouds are only seen in September or October, but Galileo was able to detect them in December, an indication of possible damage to Earth's ozone layer."
Hawkeye7(discuss) 19:20, 21 May 2024 (UTC)reply
I'm not sure we need the abbreviation of μmol/mol, as we don't ever use that unit again: on the other hand, glossing it to 'one part in a million' might be useful.
the scan platform acceleration on the spacecraft being slower than expected: this is slightly murky: do we mean that the scan platform wasn't able to move (accelerate) as quickly as the scientists thought?
It was not able to accelerate (change speed) as fast as expected.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
Thought so; would say it closer to that, then, as it's much clearer and conveys the same information. UndercoverClassicistT·
C 16:42, 18 May 2024 (UTC)reply
data acquired was to design laser downlinks: I think this should be was used to -- people designed the downlinks; the data didn't. No objection, but are we going for data as singular rather than plural?
I never use data in singular; I always use "datum". Corrected.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
I quite like the abbreviation template on HGA, but why is it there and not on any other abbreviations?
Another editor asked for it, given that the abbreviation was defined long before in the text.
Hawkeye7(discuss) 20:24, 16 May 2024 (UTC)reply
The two LGAa: this is probably the correct plural abbreviation (like LLB or pp. -- though I haven't seen a case where you decap the repeated initial), but it reads oddly: suggest perhaps spelling the abbreviation out on this occasion to avoid that?
The two LGAa were capable of transmitting information back to Earth, but since it transmitted its signal over a cone with a 120-degree half-angle, allowing it to communicate even when not pointed at Earth, its bandwidth was significantly less than that of the HGA, which transmitted over a half-angle of one-sixth of a degree, would have been: this is a long sentence: it's pretty clear up to would have been. Suggest something like than that of the HGA would have been, as the HGA transmitted....
"it looked like Galileo's only trip would be to the Smithsonian Institution.": this quote should be attributed in the text.
WP:INTEXT: " In-text attribution may need to be used with direct speech" but "should always be used for biased statements of opinion."
Hawkeye7(discuss) 20:01, 19 May 2024 (UTC)reply
Yes -- I think the combination of the quote's inherently unverifiable nature (who can disprove what "it" looked like -- that's not an empirical statement) and its strong, slightly sardonic authorial voice mean that here it really does need to be attributed. From another angle, the primary reason to include the quote, rather than a bland statement of fact like "there was a possibility that the mission would not take place", is that it is cleverly and engagingly written, and therefore it seems unfair to benefit from the author's skill and effort here while not crediting them as fully as we could. UndercoverClassicistT·
C 20:17, 19 May 2024 (UTC)reply
The reason no one had thought of it before was that the second encounter with Earth would not give the spacecraft any extra energy: the start of this sentence is verbose, and we should restate what "it" is in the new paragraph. Suggest "The VEEGA trajectory had not previously been considered because..."
I would swap the centre and left moon images around: most readers will read the left-hand one first, and it's odd that the middle one clarifies that it's of the moon when that one doesn't.
Image data collected was buffered and collected in Galileo's CDS extended memory. This represented 192 kilobytes of the 384 kilobyte CDS storage, and had been added late, out of concern that the 6504 CMOS memory devices might not be reliable during a VEEGA mission: I don't think we ever explain what CDS and CMOS mean. It's also been a while since we explained VEEGA: perhaps spelling it out, rewording it, or adding the abbreviation template would be helpful here.
Added definition of CDS, linked CMOS, added abbreviation template for VEEGA
while other data was compressed with variant of the Lempel–Ziv–Welch algorithm: data were, I think. Likewise The data collected on Jupiter and its moons was stored and, later, From subsequent analysis of this data
Two months after entering the asteroid belt, Galileo performed the first asteroid encounter by a spacecraft, passing 951 Gaspra , an S-type asteroid, at a distance of 1,604 km (997 mi) at 22:37 UTC on October 29, 1991 at a relative speed of about 8 kilometers per second (5.0 mi/s a long sentence with lots of piled-up clauses: suggest splitting into at least two.
covering about 80% of the asteroid: earlier we wrote expressed confidence that 70 percent of Galileo's science goals could still be met. -- advise consistency.
Several relatively flat planar areas were found, suggesting a catastrophic origin: can we rephrase a catastrophic origin to be clearer ("suggesting that the asteroid was formed when..."?)
Measurements of the solar wind in the vicinity of the asteroid showed it changing direction a few hundred kilometers from Gaspra, which hinted that it might have a magnetic field: grammatically, it could be either Gaspra or the solar wind.
I think it is pretty obvious, but changed "it" to "Gaspra".
Hawkeye7(discuss) 20:53, 20 May 2024 (UTC)reply
Galileo suddenly abandoned the observation configuration and resumed its cruise configuration: could amend spontaneously for suddenly to be clear that this wasn't the result of human input?
the legendary Dactyloi, mythical beings which lived on Mount Ida on Crete, after which the asteroid was named. Craters on Dactyl were named after individual dactyloi: we should be consistent as to whether Dactyloi is capitalised or not (it is in our article). You might also wish to use the English plural "Dactyls", as it's an easier jump from there to "Dactyl" for most readers.
after the legendary Dactyloi, mythical beings which lived on Mount Ida on Crete, after which the asteroid was named: slightly grammatically ambiguous as to whether after which has "the Dactyloi", "Mount Ida" or "Crete" as its antecedent.
Dactyl was the first asteroid moon discovered. Previously moons of asteroids had been assumed to be rare. The discovery of Dactyl hinted that they might in fact be quite common: this is certainly clear, but a little clunking: can we polish it for prose elegance?
Dactyl appeared to be an S-type asteroid, and spectrally different from 243 Ida, although it is also an S-type asteroid: is the antecedent of 'it Dactyl or 243 Ida? Grammatically, the former is most intuitive, though meaning-wise I think we want the latter: suggest a rephrase.
while it was en route, an unusual opportunity arose: this reads as a little bit pulp-journalism to me: is there any such thing as a usual opportunity in a mission that is inherently a one-off? I'd cut this sentence, personally, for tone.
We only need consensus to change the whole article to NASA dmy format.
Hawkeye7(discuss) 20:53, 20 May 2024 (UTC)reply
I'm not sure I understand what you mean. At the moment, the dating system is inconsistent: elsewhere, we have January 2 and 12, 1982, for example. Honestly, I'm willing to wear "NASA English" as a subset of AmerE that uses DMY dates, but we do need to pick one. UndercoverClassicistT·
C 20:56, 20 May 2024 (UTC)reply
The article currently uses mdy. I have changed the format of the dates in question.
Hawkeye7(discuss) 21:35, 20 May 2024 (UTC)reply
While Galileo was still a long way from Jupiter: any idea of how far?
When Galileo observed an impact in ultraviolet light, it lasted for about ten seconds, but in the infrared it persisted for 90 seconds or more: I'm not sure of the grammar here: the impact itself, by definition, lasted only a moment, but perhaps its traces persisted for longer?
Still need to do the last bit: will get to that when I can. UndercoverClassicistT·
C 19:36, 27 May 2024 (UTC)reply
Right, finishing off:
83 million kilometers (52×10^6 mi and following: not sure what the MoS is on this, but it's odd to mix standard-form and regular numeral notation: suggest "52 million miles", especially as we're not really in the sort of very big or very small numbers that really need SF.
I am fairly sure that it is MOS conformant, becuase it is generated by the conversion template, but dislike this form too. Just a matter of the correct incantation to get the outpuut right. Changed as suggested.
Hawkeye7(discuss) 22:53, 28 May 2024 (UTC)reply
The Galileo probe's project manager, Marcie Smith at the Ames Research Center, was confident that this role could be performed by the LGAs: I would clarify what this role was: we've just been talking about firing engines, which got me quite confused.
The dust particles were about the same size as those in cigarette smoke: could we give an actual measurement? This is good to get a feel, but I'm not sure many people would have a specific number in mind.
Usually you want the allegory. Added their approximate size.
Hawkeye7(discuss) 22:53, 28 May 2024 (UTC)reply
The existence of the dust storms had come as a complete surprise to scientists.: presumably, only when Ulysses encountered them; we should clarify that the existence of dust storms was unsurprising to the Galileo team.
data storage to the tape recorder for later compression and playback was absolutely crucial: cut absolutely: something can't be only a little bit crucial.
the radiation exceeded expectations, and nearly the spacecraft's design limits: purely for prose style, I think we need another verb after nearly: either exceeded again or a synonym.
Most robotic spacecraft respond to failures by entering safe mode and awaiting further instructions from Earth, but this was not possible for Galileo... because it would have taken too long for a signal to get there? Or had they just not added that feature? We later imply that it could, which means that we need some explanation for why it couldn't at this point.
The descent probe awoke in response to an alarm: awoke is perhaps a little anthropomorphic.
It is a technical term used in computer science. A
sleep (command) suspends execution until it is woken by an alarm.
Hawkeye7(discuss) 22:53, 28 May 2024 (UTC)reply
ammonia ice-particles : ammonia-ice particles (that is, particles of ammonia ice), surely?
ammonium hydrosulphide ice particles: by the same logic, endash after hydrosulphide. Is the British spelling of hydrosulphide intended? Sulfide is used elsewhere.
As it passed through Jupiter's cloud tops, it started transmitting data: grammatically, the antecedent of it should be the heat shield, but we presumably mean the probe as a whole.
The probe's seven scientific instruments yielded a wealth of information: at least to me, a wealth of information is a bit
WP:PUFFERY and slightly too idiomatic/flowery. Suggest showing rather than telling by just getting to what they yielded.
The implication was that the winds are not produced by heat generated by sunlight or the condensation of water vapor (the main causes on Earth), but are due to an internal heat source.: can we explain why this was a reasonable implication: presumably because Jupiter gets less energy from the Sun, being further away, yet somehow had faster winds, so the extra energy had to come from somewhere else?
No solid surface was detected (or expected) during the 156-kilometer (97 mi) downward journey.: does this really need to be said? It would have been huge news to find out that Jupiter had a solid surface, but I can't see that anyone, either then or now, would be remotely thinking of it as a possibility.
The probe detected less lightning... There was far less lightning activity than expected, only about a tenth of the level of activity on Earth. These two seem to go together, but are widely separated. Can we restructure to change that?
It orbits faster though, with a rotation period of 1.769 days: Not sure about the tone here: better and more formal as "However, it orbits more quickly..." (faster is an adjective, not an adverb, in formal writing).
More quickly is not used in formal writing, and Wikipedians deplore the use of "however".
Hawkeye7(discuss) 22:53, 28 May 2024 (UTC)reply
Where are you getting that "more quickly" isn't used in formal writing? I've never heard that "rule", and a quick ping through Google Books and JSTOR finds it in plenty of prestigious books, academic journals and so on. I've also never come across a MoS or other prohibition on "However": it's used twice in this article already. UndercoverClassicistT·
C 07:28, 29 May 2024 (UTC)reply
After a frantic effort, they managed to diagnose a problem that had never been seen before, and restore the spacecraft systems with just two hours to spare: a bit breathless (
WP:PUFFERY) in tone for me.
the flyby was very successful: in nearly all circumstances, I would advise cutting very, and would continue to do so here.
While such events were more common and spectacular on Io than on Earth, it was extremely fortuitous to have captured it: not sure this adds anything: I'd be more sympathetic if we could follow it with e.g. "because it only occurred once during the entire time-span of the mission" or something like that.
This time Galileo passed just 198 kilometers (123 mi) over the surface of Io. At this time, the spacecraft was nearly at the maximum distance from Earth, and there was a solar conjunction, a period when the Sun blocked the line of sight between Earth and Jupiter. As a consequence, three quarters of the observations were taken over a period of just three hours.: the "just"s, here (particularly) and elsewhere, read as
editorialising to me.
Unfortunately, a series of observations of extreme ultraviolet (EUV) had to be cancelled due to yet another safe mode event: likewise the unfortunately -- and another hyphen needed in safe-mode event
planetary scientist Margaret G. Kivelson, announced that Io had no intrinsic magnetic field, which meant that its molten iron core did not have the same convective: lose the comma after Kivelson. "Convective" is redlinked: is
Convection the intended target?
This time, Tvashtar was quiet: per
MOS:IDIOM, I would advise rephrasing to something that more explicitly says that the volcano was not erupting (it might have been doing so without making much noise).
Both of the sources say: "Tvashtar was quiet".
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
They might, but they don't have to follow
MOS:IDIOM: more to the point, if they use a creative idiom and we copy it wholesale when good alternatives exist, we're breaking (in a very small way)
WP:COPYVIO. We're allowed to take the facts from sources; we can't take the creative expression unless we present it as a quotation and/or attribute. UndercoverClassicistT·
C 07:27, 29 May 2024 (UTC)reply
I don't have the source in front of me, though I do have Google telling me that "Effusive eruptions are sometimes called 'quiet' eruptions". Is it absolutely unambiguous in the sources that the volcano was erupting, just not emitting a plume, other than the use of the word "quiet"? I'm not sure I can see in isolation that "the volcano was quiet" definitely means "the volcano was erupting effusively" rather than "the volcano was not erupting". UndercoverClassicistT·
C 21:37, 29 May 2024 (UTC)reply
The sources are online. Melzer (p. 254) says: "The Tvashtar volcano was quiet". This is sourced to
NASA. which says: "When Galileo sped past Io's north pole on August 6, scientists were watching for activity from a polar volcano named Tvashtar, which had been spewing a plume several hundred km high only seven months earlier. But Tvashtar was quiet."
Hawkeye7(discuss) 01:53, 30 May 2024 (UTC)reply
Our article on Tvashtar cites
this source, which makes it clear the volvcano was still erupting.
Hawkeye7(discuss) 01:58, 30 May 2024 (UTC)reply
I don't think it does: in fact, I see Streaks of light and dark deposits can be seen radiating from the central patera (volcanic crater), remnants of the now finished plume eruption, which says to me that it had finished. It does say that the volcano was still active, but that's not the same thing. Have I missed something on that page? UndercoverClassicistT·
C 07:42, 30 May 2024 (UTC)reply
"The Galileo spacecraft caught Io in the act of an active volcanic eruption on Februrary 22, 2000. Tvashtar Catena is a chain of calderas, collapse pits formed by volcanic eruptions. The active site of the eruption is visible on the left edge of the image, where infrared imaging sees the glow of a hot lava flow more than 60 kilometers long."
[4]Hawkeye7(discuss) 20:14, 30 May 2024 (UTC)reply
Although the project team worked hard to restore the spacecraft to working order, much of the hoped-for data was lost.: I'd consider cutting the first bit: this is already a very long article and section, and we surely take as read that they didn't sit back while their machine was broken?
Although the smallest of the four Galilean moons, with a radius of 1,565 kilometers (972 mi), Europa is still the sixth largest moon in the solar system: in the vein of some comments above, I'd cut still.
A "nontargeted" encounter is defined as a secondary flyby up to a distance of 100,000 kilometers (62,000 mi).: at a distance up to is more grammatical, I think. Not sure we need the quote marks: "a grandfather clock is defined as an expensive one in a tall wooden box" works fine.
Astronomer Clark Chapman argued that if we assume that a 20-kilometer (12 mi) crater occurs in Europa once every million years, and given that only about twenty have been spotted on Europa, the implication is that the surface must only be about 10 million years old.: the MoS discourages "we" in this kind of construction: suggest "argued that the surface of Europa must only be about 10 million years old, assuming..."
As I read it, the most obvious interpretation is that it contained magnesium, which I don't think is true or intended. UndercoverClassicistT·
C 07:25, 29 May 2024 (UTC)reply
Changed to "magnesium- and sodium-based salts" but note that "base" has the technical meaning of "cation" in this context.
Hawkeye7(discuss) 19:26, 29 May 2024 (UTC)reply
Since the surface temperature on Europa was a chilly −162 °C (−260 °F): that's rather below what most of us would call "chilly" (indeed, it's almost "big coat weather" up here): given the following sentence, these words can go with no loss.
Deleted. (It's not very warm here either.)
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
There was acrimonious debate among scientists over the thickness of the ice crust, and those who presented results indicating that it might be thinner than the 20 to 30 kilometers (12 to 19 mi) proposed by the accredited scientists on the Galileo Imaging Team faced intimidation, scorn, and reduced career opportunities: the chronology here seems important, but I have totally lost any sense of when this happened, or how long it went on for. Did this happen during the span of the mission itself? If not, suggest moving to a later section.
The article has switched from chronological to locational order, as Galileo returns to each Moon several times.
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
We are inconsistent about whether it's Canberra (This allowed Canberra and Goldstone to investigate the ionosphere of Europa or the Canberra (The Galileo project was able to secure 80 hours of the Canberra's 70-meter dish time.
This was the first time that a magnetic field had ever been detected on a moon contained within the magnetosphere of its host planet: does this really need all four citations?
Margaret Kivelson, the scientist in charge of the magnetometer experiment, felt that the induced magnetic field required an iron core: words for said are tricky, but felt here could perhaps cast the implication that she was working on intuition or vibes rather than professional knowledge and experience.
40 percent water ice: if we just said "ice", I don't think many readers would assume it was anything else. I think the link to
ice is an overlink.
Normally yes, but all mentions so far have been of ammonia icx.
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
NASA engineers were able to recover the damaged tape recorder electronics: hyphenate tape-recorder. On another note, there seems to be an extra line break after this paragraph.
The star scanner was observing a set of stars which included the second [[Magnitude (astronomy)]|magnitude]]: something is up with the formatting here.
The bit of wikitext with the square brackets at the end displays on the page -- you'll find it with ctrl-f. UndercoverClassicistT·
C 07:25, 29 May 2024 (UTC)reply
Delta Velorum is the brightest known eclipsing binary, brighter at maximum than even Algol.: Even is editorialising, but do I assume correctly that Algol was the previously brightest known eclipsing binary?
Delta Velorum is the brightest-known eclipsing binary, although Algol has a deeper minimum and is easier to observe visually. DEleted "even".
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
After the primary mission concluded on December 7, 1997, most of the mission staff departed, including O'Neil, but about a fifth of them remained. The Galileo orbiter commenced an extended mission known as the Galileo Europa Mission (GEM),: this is a good explanation of the GEM and GMM, which would have been much better before we got into those two moons -- we were using both of those terms quite freely, and I had rather little idea of exactly what and when we were talking about. Suggest restructuring so that this "Mission extension" section comes before what happened after the mission extension.
although it might seem wasteful to scrap a spacecraft that was still functional and capable of performing a continuing mission, Congress took a dim view of requests for more money for projects it thought had already been fully funded: this is quite strongly editorial, and needs to be rephrased to have a more neutral authorial voice.
It needs a fairly major rework: although it might seem wasteful to scrap a spacecraft that was still functional and capable of performing a continuing mission casts the strong implication that Congress were being wasteful; similarly, Congress took a dim view of requests for more money for projects it thought had already been fully funded casts them as fools, unable to see that the project had not in fact been fully funded. UndercoverClassicistT·
C 07:24, 29 May 2024 (UTC)reply
The project had been fully funded. NASA deliberately kept the price tag low in order to get funding in the first place, and there was a real possibility of the spacecraft failing before funds ran out. Deleted "it thought".
Hawkeye7(discuss) 19:26, 29 May 2024 (UTC)reply
That bit is better, but although it was wasteful to scrap a spacecraft that was still functional and capable of performing a continuing mission is still a problem. I'd be happier if someone (ideally within Congress) expressed this sentiment at the time, so we could say "although Rep. Stevenson of Ohio gave a speech in which she said...", "despite an open letter from 25 scientists arguing that it was..." or something like that. UndercoverClassicistT·
C 07:40, 30 May 2024 (UTC)reply
In order that scientists could determine whether or not native life forms existed before the planet became contaminated by micro-organisms from Earth,: this one needs a look. Firstly, whether or not is a tautology: whether is better. Secondly, as phrased, it implies that Mars has already become contaminated by microorganisms from Earth.
An alternative was the Prime Directive, a philosophy of non-interference with alien life forms enunciated by the original Star Trek television series that prioritized the interests of the life forms over those of scientists. : this doesn't seem to be relevant here, as we don't say that anyone proposed it for Galileo.
Still don't see it: I see Given the (admittedly slim) prospect of life on Europa, scientists Richard Greenberg and Randall Tufts proposed that a new standard be set of no greater chance of contamination than that which might occur naturally by meteorites, but it sounds like this is "new" relative to the 99.9% standard adopted in 1964. UndercoverClassicistT·
C 07:23, 29 May 2024 (UTC)reply
I think the numbered list in "Major findings" would be better and more MoS-friendly in prose.
NASA-ESA Outer Planets Study Team: endash, not hyphen.
Endashes are not being used for anything but page ranges. They cause more thgan enough trouble already.
Hawkeye7(discuss) 01:44, 29 May 2024 (UTC)reply
They should be:
MOS:DASH asks for them in compounds when the connection might otherwise be expressed with to, versus, and, or between. UndercoverClassicistT·
C 07:21, 29 May 2024 (UTC)reply
I know it's not an article on Juno, but is there anything we can say about what that spacecraft observed: did or will it confirm, sharpen or change any of the findings from Galileo? Are any of its research tasks shaped by the experience of Galileo?
That's my lot on a first pass. The article is certainly a monumental piece of work, and I appreciated the occasional tours into more general areas of astronomy and science when they helped explain the specifics of the mission. UndercoverClassicistT·
C 21:08, 28 May 2024 (UTC)reply
AG
Reserving a spot.
Artem.G (
talk) 19:01, 1 April 2024 (UTC)reply
First comments:
Galileo Project managers table looks broken on mobile, I'd also suggest to move it from the lead.
Pravda? Works okay on my iphone. Where do you suggest moving it to?
Hawkeye7(discuss) 20:36, 1 April 2024 (UTC)reply
Nevermind, I think it's either android or chrome quirk.
Artem.G (
talk) 06:35, 2 April 2024 (UTC)reply
Following the approval of the Voyager missions - link
Voyager program
while the legal challenge was not frivolous - why frivolous is a red link?
Not sure how it became red. Possible page move.
Hawkeye7(discuss) 20:36, 1 April 2024 (UTC)reply
It was noted that the name was also that of a spacecraft in the Star Trek television show. - maybe something like "The name also belongs to a spaceship in the Star Trek series."?
The point is that this fact was acknowledged at the time.
Hawkeye7(discuss) 20:36, 1 April 2024 (UTC)reply
and the Space Shuttle main engines (SSME) running at full power—109 percent of their rated power level.[20] Running at this power level necessitated the development of a more elaborate engine cooling system.[28] - two questions. First: full power should be 100%, so is it correct to say "at full power" here? Maybe smth like "above its full power"? I don't know the right terminology here, so maybe I'm wrong. And second: why more elaborate cooling system was needed? The engines were not designed to work at full power?
nice, makes sense.
Artem.G (
talk) 06:40, 3 April 2024 (UTC)reply
but NASA hoped to be able to recoup some of this through separate completive bidding on the two. - I'm not sure I understand what's "separate completive bidding"
the experiment was considered a resounding success and the data acquired will likely be used in the future to design laser downlinks that will send large volumes of data very quickly from spacecraft to Earth. The scheme was studied in 2004 for a data link to a future Mars orbiting spacecraft.[90] - any updates on that? It's a bit strange to see future tense about data from 1992 experiment.
At the time it was written there was not, but in December 2023, NASA's
Deep Space Optical Communications experiment on the Psyche spacecraft used infrared lasers for two-way communication between Earth and the spacecraft. Added this to the article.
Hawkeye7(discuss) 21:01, 2 April 2024 (UTC)reply
Through the implementation of sophisticated technologies - what are these technologies? And does it mean that HGA was completely off, unable to transmit anything?
Data compression software. Changed to this, with a link. HGA was rendered space junk. made this clearer.
Hawkeye7(discuss) 21:01, 2 April 2024 (UTC)reply
a total power of about 10 zeptowatts - a power of 10 should be more readable
a 1980 suggestion that the results of Galileo could be distributed electronically instead of on paper was regarded as ridiculous by geologists - just curious - it means that previously all data received from spacecraft (ie. Voyager) was printed and not stored on a tape or a computer, right?
Voyager data was stored on 8-track magnetic tape, 9-track magnetic tape and paper tape.
Hawkeye7(discuss) 21:01, 2 April 2024 (UTC)reply
thanks, never thought about that!
Its shape was not remarkable for an asteroid of its size.[110] - what is a 'remarkable shape' for an asteroid?
maybe something like "dubbed Dactyl after the legendary Dactyloi, the Ancient Greek mythical race"? Though I agree that it's also not ideal.
Artem.G (
talk) 06:40, 3 April 2024 (UTC)reply
Dactyl appeared to be an S-type asteroid, and spectrally different from 243 Ida - type of Ida is not mentioned
and telemetry from the spacecraft, travelling at the speed of light, took 37 minutes to reach the JPL - it reads like the spacecraft itself is travelling at the speed of light. Suggest to change it to "transmitted at the speed of light"
Another opportunity to observe Io arose during the GEM, when Galileo flew past Io on orbits I24 and I25, and it would revisit Io during the GMM, on orbits I27, I31, I32 and I33.[155] - what're GEM and GMM? It's explain only in Mission extension, but should be explained at first mention.
Michael Carr, a planetologist from the US Geological Survey, argued that, on the contrary, the surface of Europa was subjected to less impacts than Callisto or Ganymede.[174] - what was his justification?
I agree with Tercer, the patch looks strange, even though it is from NASA website (and was there since 1996)
The image in the article is from a NASA site (
[10]) and therefore regarded as authoritative.
In Ganymede and Callisto sections, instead of real photos there are "The internal structure" images. I think real photos would suite the article better, and I'm not sure that internal structures (as pictured) were known during the project.
The article discusses composition, so the diagrams help the reader understand the text. But there is no reason we cannot have both. Added images.
Hawkeye7(discuss) 21:01, 2 April 2024 (UTC)reply
Hey Hawkeye7, thanks for the great article and for quick fixes! I support the nomination, and it's probably the best article about a spacecraft mission that I've read.
Artem.G (
talk) 06:40, 3 April 2024 (UTC)reply
T
I'm not going to do a review, I'd just like to repeat a comment from my
Good Article review three years ago that went unaddressed: the mission patch in the infobox is hideous, and it's not the real one. It's easy to find photos of the real one online
[11][12] and since it's NASA work it should be public domain.
Tercer (
talk) 08:50, 2 April 2024 (UTC)reply
NASA's statement regarding all of its missions emblems is:
Their reproduction in any form other than in news, information and education media is not authorized without approval.
Our use falls under this Fair Use clause, but Commons disagrees.
I am will to upload a non-free image if that is the consensus here.
Hawkeye7(discuss) 21:01, 2 April 2024 (UTC)reply
WSC
Queries by WereSpielChequers. I'm enjoying reading this but not sure I know enough about the topic to do a useful review.
"Galileo performed close observations of another asteroid, 243 Ida, at 16:52:04 UTC on August 28, 1993, at a range of 2,410 km (1,500 mi). Measurements were taken from Galileo" Was 2,410 the closest approach or the point where they started taking observations? Maybe I'm wrong but my understanding of these flybys is that there is a brief period of time to take observations, and observations start and end at a greater distance than the instance of closest approach.
I have elaborated on this. It was both the closest approach and the point where they started taking observations, due to an operational problem.
Hawkeye7(discuss) 20:25, 3 April 2024 (UTC)reply
"It orbits faster though, with a rotation period of 1.769 days. As a result, rotational and tidal forces are 220 times as great as those on Earth's moon." I thought that the greater mass and maybe proximity of Jupiter to Io as opposed to the Moon to Earth would explain the tidal forces. Though perhaps we are talking about tides on Jupiter as IO also faces Jupiter so the tidal forces would presumably be explained by a bulge.
Clarified that we are talking about Io.
Hawkeye7(discuss) 20:25, 3 April 2024 (UTC)reply
That's it for now, maybe more later ϢereSpielChequers 12:25, 3 April 2024 (UTC)reply
"The orbiter was powered by 570-Watt (at launch) radioisotope thermoelectric generators (RTGs)" how many of these 570 watt generators?
There were two of them; total output was 570 W.
Hawkeye7(discuss) 03:11, 9 April 2024 (UTC)reply
"The Rogers Commission handed down its report on June 6, 1986.[47] It was critical of NASA's safety protocols and risk management" I'm assuming this was a report on the Challenger disaster, but perhaps we should say so.
For now, just some random comments. I don't know if I'll have time for a full review.
Random comments are always most welcome.
Hawkeye7(discuss) 01:37, 7 April 2024 (UTC)reply
There's many citations to Meltzer 2007. Unfortunately, the PDF accessed by the URL only includes the front matter up to page xvii. Is there a better URL that gets the whole thing?
I had that problem too, but I thought it might be a issue with my browser. Switched to the 12 January archive.
Hawkeye7(discuss) 01:37, 7 April 2024 (UTC)reply
Background:
"They were followed by the more advanced Voyager 1 and Voyager 2 spacecraft, which were launched on 5 September and 20 August 1977 respectively" Is it worth a short explanation here of why Voyager 1 was launched after Voyager 2?
Probably not, but I have added a footnote explaining that Voyager 1 reached Jupiter and Saturn first.
Hawkeye7(discuss) 01:37, 7 April 2024 (UTC)reply
Initiation:
"NASA's Scientific Advisory Group (SAG)" the acronym SAG is never used after being defined here, so no reason to have it.
"a Mariner spacecraft like that used for Voyager". I'm not 100% sure what this means. I think you mean "as was used for Voyager". The way it's written now, I could be taken to mean "of similar design".
"This allowed it to take high resolution images". Clarify what "this" and "it" refer to. Either or both could be the accelerometer, which I don't think is what you intended. It's also unclear how better attitude control affected the camera resolution, which I assume was only a function of the camera sensor.
It is easier to take longer exposures images if the camera is held still.
Hawkeye7(discuss) 01:37, 7 April 2024 (UTC)reply
Sure, but less camera motion is not the same as higher resolution. On the other hand, now that I've got the full Meltzer PDF (thanks!), I see that it does indeed say "could help maximize photographic resolution". I think that's a bizarre way to say it, but that is what the source says, so who am I to argue with NASA?
RoySmith(talk) 02:22, 7 April 2024 (UTC)reply
"Independent Agencies Appropriations Subcommittee". Many of these subcommittees have a linkable article. Is there one for this?
"Casani solicited suggestions for a more inspirational name for the project". I had to go hunting a few paragraphs back to figure out who Casani was, so maybe re-introduce him here as "project manager Casani"?
"the Galileo project's engineers decided" I think you can just say "project engineers decided" and trust the reader to understand that you're talking about the Galileo project.
Changed as suggested
"To enhance reliability and reduce costs ... This improved reliability and reduced costs" eliminate the redundancy.
"Another 165 kilograms (364 lb) was added in structural changes to improve reliability" aerospace engineers don't take on 165 kg without a good reason (famous quote: "I’d sell my grandmother for a one-pound reduction!"); is there something more we can say here about what this additional weight was used for?
I've checked all three sources, and noine are specific on this point.
Hawkeye7(discuss) 03:01, 9 April 2024 (UTC)reply
"the three-stage IUS was itself overweight" overweight compared to what? It's maximum design capacity? Some assumed weight used in early mission calculations?
"NASA decided to split Galileo into two separate spacecraft, an atmospheric probe and a Jupiter orbiter". This is confusing. Perhaps this gets cleared up later on, but at this point I'm lost, trying to figure out if we're talking about one spacecraft or two. Here, you talk about two. But in the lead, you say "the Galileo spacecraft consisted of an orbiter and an entry probe. It was delivered into Earth orbit on October 18, 1989" so that's one spacecraft.
"a signal from Earth takes anything from 35 to 52 minutes to reach Jupiter". A few points here. First, "anything" is kind of informal language. But more importantly, I'd explain the nature of this variation; i.e. it's because the Earth-Jupiter distance varies depending on where they both are in their orbits; readers who are not familiar with how this stuff works might guess it has to do with other factors like varying amounts of power available on the spacecraft, or whatnot. Also, I think these sorts of things are typically cited as round-trip time because that's what really matters if you're trying to do remote control; downlink delay to send telemetry, plus the uplink delay to send a command based on the telemetry you received.
"autonomous spacecraft,[35] which was a necessity for deep space probes," There's something odd about the grammar here, but I'm not sure what. Maybe "were a necessity" (or, just "were necessary")?
As a generic comment, you use "flyby" many times in the article, but never explain what it is. For the benefit of our readers who don't know anything about spaceflight, you should explain what a flyby is the first time it's used in the main body.
Even more generically, please read through the entire article looking for technical words and consider whether a naive reader would understand them. As an example, you talk about "the orbiter in February 1984 with the probe following". How does an orbiter differ from a probe? Other words that might need explaining include "autonomous", "attitude" (we don't want to be launching any spacecraft in a bad mood!) but those are just a few examples, I'm sure you'll find more.
Still talking generically, it might be a good idea to give real-life examples of units that a reader might be unfamiliar with. For example, "a lithium–sulfur battery rated at 730 Watt-hours"; it would help the reader understand this better if you said that was about how much energy is in a typical car battery (but please double-check me on that and find a
WP:RS)
On average, a 12-Volt car battery can maintain about 5 Amperes for ten hours. That makes such a battery a 50 Ampere-Hour battery. That is equal to around 12 x 50 = 600 Watt-Hours. No idea if
this is a reliable source.
Hawkeye7(discuss) 19:21, 9 April 2024 (UTC)reply
(my apologies for these comments comming in dribs and drabs)
"general-purpose heat source radioisotope thermoelectric generators (GPHS-RTGs)"
WP:SEAOFBLUE. I suggest only linking to
GPHS-RTG, and let people drill down from there if they want more details.
"generated 570 Watts at launch ... rated at 730 Watt-hours." I'm not sure how to handle this better, but it's jarring to have two consecutive sentences talking about power sources using different units (power vs energy). I understand the difference, but I suspect a less technically savvy reader will just be confused and/or come away with the wrong impression that the battery is "bigger" than the RTG, when in fact those values can't be compared in any useful way. I see that you're just giving the data as it's presented in the NASA report, but it would still be nice if there was a better way to present this. Actually, a quick calculation says average of 520 watts x 8 year = 36 MW-Hrs. Upon reflection, this makes sense; the battery only runs the atmopheric probe for the short time it takes to descend and burn up. Hopefully you can find some RS that goes into this sort of analysis so you can present it in the article.
This still needs to be addressed.
RoySmith(talk) 22:38, 17 April 2024 (UTC)reply
"Heavy Ion Counter." Why the upper case?
A holdover from the original version, which used this form. After a change in the MOS (
MOS:EXPABBR) in 2017, I and other editors went through the article and removed the uppercasing of abbreviated forms. De-capped.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
Reconsideration
"flight tore the spacecraft apart" seems like an unencyclopedic way to phrase that. Maybe something like "Resulted in loss of the vehicle and the deaths of ..."
There was a debate about this in one Challenger disaster article. Some people wrote that the spacecraft exploded when it was actually torn apart by aerodynamic forces. This article follows the more precise wording chosen over there.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
"This was only partly due to the NASA management's increased aversion to risk in the wake of the Challenger disaster; NASA management also considered ..." This appears to be based on a p 217 quote from Marty Winkler of General Dynamics commenting on his interpretation of NASA management's decision. So I think this deserves attribution as Winkler's opinion.
Is is the opinion of historians Virginia Dawson and Mark Bowles.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
OK, so it needs some attribution, "According to Virginia Dawson and Mark Bowles ..."
RoySmith(talk) 22:40, 17 April 2024 (UTC)reply
"for a time it looked like its next trip would be to the Smithsonian Institution." That's a cute way to phrase it, but maybe it should be stated a bit more formally. Also, it's an unattributed quote from the source, so that's a problem.
Altered to match the quote, and turned into a quotation.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
"southerly declination of −23 degrees" -> "declination of 23 degrees south" Likewise for "northerly one of +18 degrees"
"Furthermore ... so the main tracking station would be the Canberra Deep Space Communication Complex in Australia". That makes it sound like using Canberra is a problem. Is it? Why?
Redundancy. There was only one complex in the southern hemisphere but two in the northern. Expanded on this.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
Nuclear concerns
"plutonium in the Galileo's radioisotope thermoelectric generators (RTGs) and General Purpose Heat Source (GPHS) modules" This makes it sound like these are two different things, each with their own plutonium supply. My reading of
GPHS-RTG leads me to believe this is a single unit with a single plutonium supply which performs both functions, so this needs to be clarified.
Correct. Changed to "Galileo's GPHS-RTG modules
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
The overall tone of the first paragraph seems in violation of
WP:NPOV. You minimize the risk ("what they perceived as an unacceptable risk") and then state in wiki-voice that "They had been used for years in planetary exploration without mishap", implying that there is indeed no risk.
There is a whole paragraph about the risk. The issue is what degree of risk is "unacceptable".
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
" If the Galileo/IUS combination fell free of the orbiter". Missing a word? of -> from, perhaps?
Looks okay to me, but changed "of" to "from"
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
Ugh. I must be becoming dyslexic. I read that as "free fell", as "the RTG was in free fall". My bad.
RoySmith(talk) 00:15, 14 April 2024 (UTC)reply
"an accident might have released up to 11,568 curies (428,000 GBq)." Another example of a unit which is almost certainly unfamiliar to most of our readers. Is that a lot? Are we talking a couple of dental X-ray's worth or another Chernobyl? Likewise with "NASA concluded that the chance of such a disaster was 1 in 2,500". I have no idea if that's a lot compared to all the other risks. NASA must have some standard risk analysis budget. How does this compare with other missions? Also, what does "such a disaster" refer to? In ther previous paragraph you give two different scenarios; which of those is this?
Chernobyl released between 50 and 185 million curies; three mile island released about 2.5 million curies. I have no figures on the risk assessments of other missions. Part of my job involves carrying out risk assessments, and the low odds and moderate consequences would mean approval. Linked the unite. Deleted "such".
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)+reply
Launch
"There were fears that the spacecraft might be hijacked by anti-nuclear activists or terrorists". I'm guessing this is due to the plutonium, but please don't make the reader guess. As an aside, I also have to wonder about the risk was of sleep-deprived truck drivers in a high speed convoy over an unfamiliar route at night having a crash. :-)
"three hours into the flyby, the tracking station at Goldstone had to be shut down due to high winds" If it was being tracked by Canberra and Madrid, why did it matter what was going on at Goldstone? I'm guessing the answer is that by the time three hours had passed, Goldstone had become the active station, but that should be explained for the benefit of our less technically savvy readers. It also seems odd that you give the time of the flyby down to the second ("05:58:48 UTC") implying it's a discrete moment in time, then later talk about being three hours into it. Maybe just note that 05:58:48 was the time of closest approach?
Clarified. Note that 10 February in Canberra and Madrid was only 9 February at JPL.
Hawkeye7(discuss) 21:36, 13 April 2024 (UTC)reply
Maybe I'm just missing it but I don't see where you explained this.
RoySmith(talk) 22:53, 17 April 2024 (UTC)reply
"Galileo's closest approach to Venus came at 05:58:48 UTC on February 10, 1990, at a range of 16,106 km (10,008 mi)."
Hawkeye7(discuss) 23:58, 17 April 2024 (UTC)reply
You might also want to explain that doppler provides a direct measurement of the relative velocity between two bodies (in this case, Galileo and the Earth). Again, this is something our more sophisticated readers will know, but will leave others struggling to understand.
Yeah, but I think it would still be better to provide some explanation here. I suspect most people are familiar with the "train whistle gets lower in pitch as the train passes" demonstration, but I don't think they would necessarily make the leap to "by measuring the change in carrier frequency of the spacecraft's transmission compared to the nominal frequency, you can compute the spacecraft's velocity relative to Earth", and
Doppler effect isn't much help for the casual reader trying to figure that out. Likewise, they might have heard of "Doppler radar" in the context of some gizmo the cops use to give you a speeding ticket, but I think it's asking a lot to expect the casual reader to understand the application of that to space navigation.
RoySmith(talk) 00:27, 14 April 2024 (UTC)reply
"Earth's strong magnetic field causes this to occur ... from its center," it's unclear what "this" and its" refer to. I think you're talking about the Earth's bow shock, and the Earth's center, but clarify.
"causes the bow wave", I assume "bow wave" and "bow shock" are synonyms, but perhaps reduce confusion by just using the same term in both places.
Used "bow shock" consistently.
Earth encounters
"Galileo made two small course corrections on 9 to 12 April and 11 to 12 May 1990". The source says, "TCM4 was the largest course correction that Galileo would have to perform", which seems at odds with your statement that they were "small".
"the first time that a deep space probe had returned to Earth from interplanetary space." this is almost word-for-word from the source and is thus a
WP:CLOP violation. Either rephrase in your own words or make it a direct quote.
"The opportunity was taken to conduct a series of experiments." This sentence only makes sense when read in the context of the section heading; it should stand on its own.
"another groundbreaking experiment was performed" in who's opinion was it groundbreaking? And since this is "another groundbreaking experiment", what were the other(s)?
Probably the sources, which are often written in American English. Deleted "groundbreaking".
Hawkeye7(discuss) 00:13, 14 April 2024 (UTC)reply
"at a wavelength of 532 nm" I'll admit to not understanding most of
Nonlinear optics, but I assume if the frequency doubled, the wavelength is halved, which leads me to wonder if 532 nm is the wavelength before or after the frequency doubling.
"Cassegrain telescope" link to
Cassegrain reflector (I assume that's the right target). I've never heard of using a telescope to transmit an optical beam, but obviously the optics are symmetric, so I assume you put the laser into "eye" end, but it might be worth clarifying that.
The source says: "coupled to a Cassegrain telescope through a coudé mount arrangement."
Hawkeye7(discuss) 00:13, 14 April 2024 (UTC)reply
"produced images of Earth clearly showing the laser pulses" did they just detect the pulses, or was data actually communicated over this carrier?
Just detected. The article goes on to describe subsequent work on laser communications.
Hawkeye7(discuss) 00:13, 14 April 2024 (UTC)reply
High gain antenna problem
"Once Galileo headed beyond Earth, it was no longer risky to employ the HGA", HGA was defined several sections earlier; it might be useful to re-introduce where what the acronym means.
"They would drive a worm gear." Not clear what "they" is; probably "the actuator motors", but this and the previous sentence could be combined and rephrased to make that more clear.
"the spacecraft's spin rate had decreased" I assume this was due to the increased moment of rotational inertia? If so, it would be good to explain that (assuming a RS says so).
"so after five deploy and stow operations, the DDA torque was half its original value" This is confusing. Previously you said they didn't try to refold it, and now you're saying they tried five times. Something's amiss here.
Nothing is amiss; they did not try to refold it. Deleted the (correct and sourced) sentence to remove any confusion.
Hawkeye7(discuss) 00:13, 14 April 2024 (UTC)reply
"during the 4.5 years that Galileo spent in storage ... eroded and worn by vibration during the three cross-country journeys by truck" So, did the damage happen during storage or during truck rides?
"since it transmitted a signal isotropically" this is confusing. Earlier you talk about swinging LGA-1 and LGA-2 to their hard stops, which implies some kind of aiming capability. But now you're talking about isotropic radiation, which to me says it's not aimed in any particular direction. This should be clarified.
Looks like you have found an error in the source. Corrected.
Hawkeye7(discuss) 00:13, 14 April 2024 (UTC)reply
I don't understand what "which transmitted over a one-sixth half-angle" means. One-sixth of a degree? One sixth of the beamwidth of the LGA? Also, in "its bandwidth was significantly less", I'd be specific and say "data bandwidth" or "digital bandwidth", or even better, "data rate" to avoid confusion with
Bandwidth (signal processing).
RoySmith(talk) 14:39, 14 April 2024 (UTC)reply
Also, "The two LGAa were capable of ... but since it transmitted its signal" plural/singular inconsistency.
RoySmith(talk) 14:40, 14 April 2024 (UTC)reply
And, "but since it transmitted its signal over a cone with a 120-degree half-angle ... its bandwidth was significantly less than that of the HGA," implies that the beamwidth was the only cause of the reduced data rate. In reality other causes were reduced transmit power and (if I'm reading this right) the need to use a smaller aperture receiving antenna on S-band.
RoySmith(talk) 14:45, 14 April 2024 (UTC)reply
Typo. It should have been "a half-angle of one-sixth of a degree". Corrected.
Hawkeye7(discuss) 21:57, 14 April 2024 (UTC)reply
You also should say some more about how they switched to a better compression algorithm. The JPL source says "By programming a software (11,1/2) convolutional code on a Galileo compute". I assume this meant they had the ability to upload new software to the spacecraft, which certainly deserves at least some explanation.
RoySmith(talk) 14:50, 14 April 2024 (UTC)reply
Yes, they had the ability to send software updates.
Hawkeye7(discuss) 21:57, 14 April 2024 (UTC)reply
Added a bit about the compression algorithms used.
Hawkeye7(discuss) 05:14, 15 April 2024 (UTC)reply
"Conservatism was not restricted to engineers ... putting a wooden ruler up to the screen." This sentence seems out of place for this section.
Storage was expensive in the 1980s. The organization I worked for abandoned plans to put five years data online in favour of just 12 months because each month required a disk that cost $20,000 at the time, so that saved nearly a million dollars. A decade later, I bought the 48 disks for $200 each on my corporate Amex card.
Hawkeye7(discuss) 21:57, 14 April 2024 (UTC)reply
"Perhaps the most surprising feature was several relatively flat planar areas" Who is making the editorial judgement about how surprising this is? "According to Joe Scientist, the most surprising feature was..."
"Galileo suddenly abandoned the program and resumed its cruise configuration." Unclear what that means. What is "the program"? Does resuming it's cruise configuration mean it attempted to undo the course correction, or powered down the instruments it was going to use for observing, or something else maybe? Also, "suddenly" sounds like editorializing, so attribute: "Fred Flight Controller said the configuration change happened suddenly".
"Measurements were taken from Galileo using SSI and NIMS" Drop "from Galileo". Of course they were taken from Galileo; there's no other possible place they could have been taken from.
"The requirement to use the LGA resulted in a transmission rate of 40 bits per second." You've said this already in a previous subsection, so no need to repeat. Or maybe something like: "At this time, the LGA was still only running at the 40 bps data rate available during the Gaspra flyby", which gives the reader some context about where they were in the ongoing efforts to increase the data rate.
"A tiny Doppler shift in the signal of the order of a few centimeters per second" This seems like a weird mixing of units. Doppler shift is a change in frequency. From that you can compute a velocity. So, "A velocity change of a few centimeters per second, as measured by Doppler shift".
"it was fired for the first time" Perhaps I'm picking nits here, but was it ever test fired on Earth? If so, "fired for the first time in XX years", or "after completing its manufacturing tests", or whatever. It's certainly possible this was its first firing ever; some engines are never test fired before a mission, but some are.
"The main engine could not be tested or fired prior to release of the atmospheric probe because the probe was mounted in front of the engine nozzle."
Hawkeye7(discuss) 21:57, 14 April 2024 (UTC)reply
"it would perform as a communications relay": maybe "perform" -> "act" ?
" The Galileo probe's project manager ... this role could be performed by LGA-1" This sentence is awkwardly placed. The previous sentence talks about firing the engine, and the next sentence talks about how that firing changed the velocity, but this sentence has nothing to do with the engine.
The engine was fired to place the orbiter in a position to act as a relay for the probe.
Hawkeye7(discuss) 21:57, 14 April 2024 (UTC)reply
The "Isbel, Douglas; Wilson, James H. "Galileo Flying Through Intense Dust Storm" (Press release). NASA/Jet Propulsion Laboratory. 95-147. Retrieved November 16, 2020. URL can't be reached.
"The bow shock was not stationary, but moved to and fro in responses to solar wind gusts" "not stationary" is redundant with "moved". Also, responses -> response
" Most robotic spacecraft respond to failures by entering safe mode ... not possible for Galileo.[136]" You've already discussed the need for autonomous operation in Preparation; no need to go over that again here.
"The descent probe awoke in response to an alarm" the word "alarm" sounds like there was some kind of failure that it was responding to. Maybe "timer" wou;d be a better word?
"Alarm" is more technically correct. In computing, an alarm is for a clock time, whereas a timer is relative to the CPU cycles.
Hawkeye7(discuss) 20:32, 15 April 2024 (UTC)reply
"encountered a previously undiscovered belt of radiation ... Before the atmospheric entry, the probe detected a previously unknown radiation belt". Is this two different belts? Needs to be clarified one way or the other.
There is only one; the sources confused the article writer.
Hawkeye7(discuss) 20:32, 15 April 2024 (UTC)reply
You use "bars" as a unit. I'm pretty sure it's not supposed to be pluralized, i.e. "1.5 to 2 bar". I also don't see the point of {{convert}} here; that's useful for metric-english conversions, but bar -> kPa doesn't add anything of value.
"bars" is correct. Surprised that it converted to kilopascals; removed the conversion as unecessary.
Hawkeye7(discuss) 20:32, 15 April 2024 (UTC)reply
"The probe slowed to subsonic speed" It's not clear what "subsonic" means in this context. I assume we're talking about below the speed of sound in the local Jovian atmosphere? If so, clarify that, and give a number for what Mach 1 is in those conditions.
Checking the sources, I find that Mach 50 is 170,000 kph, which we already said. I find Mach confusing in this context myself, although it is sourced, so removed.
Hawkeye7(discuss) 20:32, 15 April 2024 (UTC)reply
"which would then take days to arrive using the LGA" maybe "to be transmitted" instead of "to arrive"?
"it entered a 198-day parking orbit" link
Parking orbit. Also, it's not clear what 198 days refers to. Is that how long it was in orbit, or how long a single orbit took?
" Only the fields and particles instruments were allowed to collect data, as these required the tape recorder to run at slow speeds, and it was believed that it could handle this, whereas the SSI camera required it to operate a high speed, with abrupt stops and starts." This is almost word-for-word from the source. See
WP:CLOP.
"When Galileo next approached Io on I25 at 20:40 Pacific Time" I get that the source you're citing uses Pacific Time, but you're using UTC everywhere else, so convert to UTC.
"Galileo flew past Io on arrival day" explain what "arrival day" is, probably under the "Arrival" section above. There's a bunch of possible days that could be called that (arrival at the bow shock, closest point of approach to Jupiter, entering orbit, etc)
"As a consequence, three quarters of the observations were taken over a period of just three hours." I don't understand why this is a consequence of there being an Earth-Sun conjunction.
Galileo cannot be received when the line of sight is blocked.
Hawkeye7(discuss) 04:49, 16 April 2024 (UTC)reply
Yeah, but that only affects transmitting data to Earth. Observations can still happen and record the data on tape, so I still don't see how one is a consequence of the other.
RoySmith(talk) 17:47, 16 April 2024 (UTC)reply
"The I24, I25 and I27 encounters had been on equatorial orbits, which made it difficult to determine whether Io had its own magnetic field, or one induced by Jupiter" why does being in equitorial orbit make this difficult? And, are we talking about Jupiter's equator or Io's equator?
Source says: "All of our previous magnetic measurements at Io have been on equatorial passes, and from those we can't tell whether the field at Io is induced by Jupiter's strong magnetic field or produced by Io itself". No idea why.
Hawkeye7(discuss) 04:49, 16 April 2024 (UTC)reply
"but data transmission was hindered by a Solar occultation" link to
Occultation
"with a diameter of 5,270 kilometres" you describe the other moons by their radii. Pick one and use it consistently. Also, be consistent about kilometres vs kilometers.
"strength of about 750 nanoteslas (0.0075 G)" Tesla and Gauss are both SI units; no need to show both. But it would be useful to compare this to the strength of Earth's magnetic field, since most readers will have no clue how big a Tesla is.
"This discovery led naturally to questions about its origin." "This" and "its" both refer back to the previous paragraph. Maybe just combine the two paragraphs.
"enabling a higher bit rate despite the spacecraft's long distance from Earth", Drop the "despite ...." clause; the larger aperture allowed for a higher bit rate regardless of all other factors. The biggest problem here was that the HGA was inoperative; the transmission distance was exactly what was expected during mission planning.
"predominantly >2 MeV (0.32 pJ) electrons" Is there any reason to convert to J? I would think MeV would be the universally used unit of measurement here.
They are, but...
MOS:CONVERSIONS: "For units of measure that are ... not part of the SI or US customary systems... supply a parenthetical conversion into at least SI units." Electron volts are
Non-SI units mentioned in the SI, hence a conversion is supplied.
Hawkeye7(discuss) 20:13, 16 April 2024 (UTC)reply
"Galileo impacted Jupiter in darkness just south of the equator" What does it mean to "impact" something made of gas?
The sources consistent use the term, and we have a whole article on
impact events on Jupiter that does not define it. But at some point it gets so dense that it is like hitting a solid surface.
The astronomers inform me that this is the case on Earth too; "impact" is 50-80 km up, not on the surface.
Hawkeye7(discuss) 05:22, 6 May 2024 (UTC)reply
"Galileo had not been sterilized prior to launch and could have carried bacteria from Earth." link sterilized and bacteria.
OK, finally got to the end. So much for "just some random comments" :-) I'm going to give this a rest for a bit then come back and see how things look overall.
Second pass
The orbiter would be in orbit around Jupiter when the probe arrived, allowing it to perform its role as a relay." It's unclear what "it" refers to: the orbiter or the probe.
I thought it was clear enough, but changed it to "the orbiter".
Hawkeye7(discuss) 00:25, 18 April 2024 (UTC)reply
"required a second Space Shuttle mission and a second carrier to be built for the probe" What is the carrier? I'm guessing it's some mounting adapter that lets you install the probe into the shuttle cargo bay, but clarify.
No, it is a spacecraft. The probe wasn't intended to fly to Jupiter by itself. Clarified this.
Hawkeye7(discuss) 00:25, 18 April 2024 (UTC)reply
"NASA hoped to be able to recoup some of this through competitive bidding." You put that in just for comic relief, right?
The source says ""Delaying to 1984 is more cost efficient because we can go into more competitive bidding for the carrier."
Hawkeye7(discuss) 00:25, 18 April 2024 (UTC)reply
"President pro tempore of the Senate" I don't think I've ever seen this spelled out in full, it's always just "president pro tem", so that's probably what we should use here.
At this point, the lack of ALT text is the only thing holding me back from supporting this.
RoySmith(talk) 12:07, 19 April 2024 (UTC)reply
The ALT for
File:Galileo atmospheric probe.jpg got cut off (I assume there should be a number at the end), but that won't keep me from supporting. Overall, an interesting article. Thank you for submitting it, and for putting up with my nit-picking.
RoySmith(talk) 17:19, 25 April 2024 (UTC)reply
Sorry, meant "non-direct" link. As in, a link to the webpage where you found the image, not a link to the image itself. Such direct links can be hard to repair when they break, and the information the link is there for (e.g copyright statements) isn't on the file page.
Jo-Jo Eumerus (
talk) 08:20, 26 April 2024 (UTC)reply
A link has been added to the page where I found the image.
Hawkeye7(discuss) 15:12, 26 April 2024 (UTC)reply
Source review-wise, I am checking
this version; spot-check upon request. #44, #71, #75, #150, #175, #204 are broken. #177 can probably get a better source information than a raw URL. What makes #224 and #225 a reliable source? I am wondering about spaceflightnow.com too, since they don't give much information on themselves. I presume the differences between various sources with respect to identifiers are b/c some of them have identifiers and others don't? That needs doublechecking as e.g Cowen 2001 doesn't have the doi 10.2307/3981750 shown.
Jo-Jo Eumerus (
talk) 13:01, 25 April 2024 (UTC)reply
#44, #71, #75, #150, #175, #204 have the archive URL added.
Hmm? The only mention of Spaceflightnow.com is when it is compared to a different source.
Jo-Jo Eumerus (
talk) 08:20, 26 April 2024 (UTC)reply
I consider Spaceflightnow.com a reliable source for Spaceflight news. We can ask at the
WP:RSN.
Hawkeye7(discuss) 12:47, 26 April 2024 (UTC)reply
It's not clear to me what editorial oversight Spaceflight Now provides, and that's what determines if it's a RS or not. They have a "Member Content" section (
https://spaceflightnow.com/category/members/); I'd be wary of using anything from there (not that you have). Looking at the four citations to Spaceflight Now, two ("Galileo to fly over source of recent polar eruption on Io" and "Galileo data recorder still not working") are NASA/JPL NEWS RELEASE, so clearly no problem with those as far as RS goes, but the citations are wonky; they should have NASA/JPL as the publisher and Spaceflight Now noted as the content deliverer using the "via" attribute (or find the originals on a NASA site). "Galileo spacecraft crashes into Jupiter" is by Peter Bond who has published several books through reputable publishers (
https://peterbondspace.com/) so I'm inclined to accept him as a RS based on
WP:EXPERTSPS. "The Galileo trials" by Ben Evans I'm less sure about. He's described as "a schoolteacher and freelance astronomy and space exploration writer", so I'll need some more convincing to accept him as an expert.
RoySmith(talk) 16:42, 27 April 2024 (UTC)reply
I have replaced the two press releases with links to the associated NASA/JPL press release pages and removed the Ben Evans reference.
Hawkeye7(discuss) 02:03, 28 April 2024 (UTC)reply
Now that it's added, yes. I just wonder if there are other sources that could have DOIs added.
Jo-Jo Eumerus (
talk) 08:20, 26 April 2024 (UTC)reply
I added the doi in December 2020 (
[14]). Are we talking about the same link? Usually I rely on the citation bot to add them.
Hawkeye7(discuss) 12:47, 26 April 2024 (UTC)reply
Nevermind that, I have no idea what I was seeing there.
Jo-Jo Eumerus (
talk) 13:57, 26 April 2024 (UTC)reply
Hi
Jo-Jo, are we good on either or both of those reviews? Cheers.
Gog the Mild (
talk) 14:26, 14 May 2024 (UTC)reply
"Ames and JPL decided to use a Mariner spacecraft as was used for Voyager for the Jupiter orbiter...": Wouldn't "Ames and JPL decided to use a Mariner spacecraft also used in the Voyager for the Jupiter orbiter" be more clarifying and less confusing?
"In December 1984 Casani proposed adding a flyby of asteroid 29 Amphitrite to the Galileo mission. In plotting a course to Jupiter, the engineers were concerned to avoid asteroids": Consider rewording to "In December 1984, Casani proposed adding a flyby of the asteroid 29 Amphitrite to the Galileo mission. In plotting a course to Jupiter, the engineers were concerned about avoiding asteroids."
That would be ambiguous. Changed to: "In plotting a course to Jupiter, the engineers wanted to avoid asteroids."
Hawkeye7(discuss) 20:24, 22 May 2024 (UTC)reply
"the lightning activity: Consider removing the "the" prefix?
I'm not sure about this, but consider linking to high energy particles, heavy ions, and multispectral imaging so readers can have an idea of what these are?
In quite a few places, proper article prefixes are not there, I have noted down some of these here. Would it be ok with you if I made these minor edits myself?
Happy to extend my support for promotion to FA. Cheers
Matarisvan (
talk) 18:43, 25 May 2024 (UTC)reply
Overall, a very good article, sources are great.
Drive-by comments
Cites 72 and 73 should be pp, not p; and have en dashes, not hyphens.
Not page ranges; these pages are numbered with hyphens.
Hawkeye7(discuss) 19:11, 4 June 2024 (UTC)reply
No publisher location for Harland or National Research Council; European Space Science Committee (1998)?
Gog the Mild (
talk) 10:53, 31 May 2024 (UTC)reply
Closing note: This
candidate has been promoted, but there may be a delay in bot processing of the close. Please see
WP:FAC/ar, and leave the {{featured article candidates}} template in place on the talk page until the
bot goes through.
Gog the Mild (
talk) 19:21, 4 June 2024 (UTC)reply
The above discussion is preserved as an archive. Please do not modify it. No further edits should be made to this page.