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Should this be added to the page?
Exotic cause of 'Pioneer anomaly' in doubt
I'd do it, but I can't be bothered to absorb the entire page well enough to put this in the right place. :)
—
Aristotle
11:48, 22 June 2007 (UTC)
This used to be on the page, though in a paper by Iorio rather than the paper referenced in the article (though they have exactly the same conclusion). I checked and it was removed by an anonymous editor 63.130.192.57 on 25 May, while also removing some more dubious stuff. I've re-added it to the possibility of gravitational causes. LouScheffer 15:33, 22 June 2007 (UTC)
According to Alan Stern, prime investigator of New Horizons space probe (former Pluto-Kuiper Express), this probe will be spin-stabilized during cruise and thus his radio team is hoping to look for the Pioneer Anomaly in their data. -- Mandevil 09:15, 24 Feb 2005 (UTC)
' As far as i have heard, the radiation pressure from the rtg should mask the 'anomaly' for new horizons. nevertheless, people might try to use the REX instrument (which is basically a radio transmission expreriment as a "probe") and to compute precisely the thermal radiation pressure.
a recent reference for that : New Horizons and the Onset of the Pioneer Anomaly, Michael Martin Nieto http://arxiv.org/abs/0710.5135v1
OK, added this to the article. -- LouScheffer ( talk) 21:16, 16 November 2007 (UTC)
I just wonder have the scientists accounted for Sol gravitational well when estimating the drift? What i mean is that electromagnetic wave increase/decrease in frequency when escaping/incoming the gravity center
one more thing to be careful about is the speed of the pioneer - how big the relativistic effects are at that speed (time dilation) - have this effect been accounted for?
one more question - "The drift can be interpreted as due to a constant acceleration of (8.74 ± 1.33) × 10−10 m/s2 directed towards the Sun." could this be caused by the masses of all the planets and asteroids in the solar system (especialy the Jupiter) ?
Regarding your questions: yes, the gravitational Doppler effect has been accounted for in the calculations, and introduces a negligible correction which cannot explain the anomaly. This is a standard procedure in telemetry and Doppler analysis of any spacecraft.
Also, the crafts are travelling at a speed that is many order of magnitudes lower than the speed of light, so that time dilation cannot account for the effect. Furthermore, since the effect reveals itself through the unexplained Doppler shift, the relevant relativistic correction is the aforementioned gravitational Doppler effect.
Finally: although the numbers don't match, it could be possible that, at a certain time and position throughtout its voyage, the probes were subject to a gravitational pull from Jupiter and other bodies that equals the anomaly. However, the key word here is "constant acceleration": all gravitational forces decrease with the inverse of the distance squared, so it appears impossible to describe a constant effect through it. And, of course, all known gravitational effects were previously accounted: NASA engineers do mean business (Anderson et. al.)!
A slightly more convoluted discussion involves the gravitational force due to objects in the Kuiper belt. It has been shown (Bertolami and Vieira) that only a exceedingly odd density profile for these objects could approximate the effect, and even so only within a narrow region of space.
Hope I was of some help.
Jorge
Thomas your page has one additional piece of information, that the beam of the antenna is not wide enough to deduce anything but a earth directed acceleration, if that is true the story is possibly a hoax , as it tends to digress to sun-pointing accelleration instead. Anyway i can imagine gravitational drags or magnetic shifts of some influence, I would also not be surprised if it was the shadow of the antenna. perhaps the relevance of the earth magnetic field naturally gets more pronounced on certain trajectorys but i would think that had very limited windows.(1g per au is suggestive) I don't know in how far metal molds correspond to the overall earth magnetic field(not to bad i think) and i can't imagine it would matter this much(the flyby effect seems the effect of earth magnetic (gravitational) variation but i dont know if that could induce that variety, i would think yes since the effect is small and the earth is big, perhaps eg. it matters if the part you fly over is warm). 77.248.56.242 23:34, 13 June 2007 (UTC)
The wrong sign? Please explain
"The pressure of sunlight is too small at this distance, and the wrong sign, as are the spacecraft's radio emissions"
You mean, "and is on the wrong side"?? -- 129.139.18.18 18:54, 9 April 2007 (UTC)
I removed today (April, 18, 2007) the likely self-promoting external link to [1], compilation of JPEG files of non-peer-reviewed scanned manuscripted work (see the historic to see when and how it had been added, November 2006). Nevertheless, I have no clue in physics, so it would be useful that anyone a bit more aware than I am have a look at his page and see if the link needs be added once more.
Someone took issue with my addition of a link to Alexander Mayer's The Many Directions of Time, so I thought I'd expand on it a little here. First, I have absolutely no connection with Mayer other than having read his work. Yes, it is a self-published ebook. However, the transverse gravitational redshift theory is firmly grounded in general relativity and makes many empirically testable predictions. This is the hallmark of a good scientific hypothesis. If this was obvious quackery such as Time Cube removing it would be justified, but that's not the case here. Whether Mayer is right or wrong, removing a reference to a possible explanation because you don't like the web page is, in my opinion, a disservice to Wikipedia readers.
I'll try to address each of your points.
In summary, I have no idea if Mayer is right. He may well be wrong. But I find his claims and supporting data compelling enough to warrant some investigation. Given the plethora of empirically testable predictions made in the book, some enterprising experimentalists ought to be able to discover whether or not Mayer is on to something - but for that to happen, they have to at least be aware of the theories, hence my motivation for making the information available. The list we are editing is called "Possible explanations", not "Ironclad explanations" and all of the new physics portion involves controversial modifications to current theories. I don't see why Mayer is any different in that regard. I'll say one thing - he seems to be doing a heck of a lot better than the superstring theorists at making testable predictions.
The case you are talking about (two clocks each perceived as running more slowly than the other) is extremely common within Einsteinian special relativity - that's how relativistic time dilation works. If one observer is moving at high speed relative to another and each are transmitting clock data, they will perceive each other's clocks as being slower than theirs. Do you also assert that special relativity is wrong? I think the problem with your scenario is that you are making the assumption that there really is a consistent universal time axis that you can measure against, which is just not the case for Mayer's geometric time or for relativistic time dilation. It defies common sense, but each observer really will have different tick counts because the perceived frequencies of each clock is not the same. In fact, if you read Mayer's work you find that the whole concept of geometric time is rooted within special relativity, much as TGR is rooted in general relativity. Pheran 15:39, 28 June 2007 (UTC)
Dear editors, the data provided below was added earlier into the article, in the related section, but then removed with the comment "ESA ref does not mention pioneer, second ref is another self-published TOE by a non-scientist". Well, although the ESA link, 2006, does not mention the pioneer anomaly it does demonstrate the possible deviations from Einstein-Newtonian law of gravitation that Kunst's paper already in 1999 refers as being measured in laboratory and at astronomical scale; the second ref as you may very well deduce, and as it is known by several "relativity" editors around, it is a 2002 paper from a scientist with a highly reputable background, yet a taboo among the academic physics community (ask yourselves why!):
Obviously, from my past editing experiences here at Wikipedia there seems to be many individuals around not interested that the lay public becomes acquainted with these other perspectives within the scientific community. Friendly. —The preceding unsigned comment was added by 213.58.99.92 ( talk • contribs) 23:17, 23 July 2007 (UTC).
In line with WP:BOLD, I am removing a pile of external links that I think are better not in the article. If someone, after double checking relevant wikipedia guidelines, feels that some of these should be restored, do please feel free to revert individual links as you see fit. If this occurs, I will not revert back. I may tag the link, and engage discussion here.
Here are links I have removed.
These are the links that remain.
— Duae Quartunciae ( talk · cont) 22:17, 29 July 2007 (UTC)
Maybe I did the math wrong, but a force of (8.74 ± 1.33) × 10^−10 m/s2 across 35 years (1.10449241 × 10^9 seconds) works out to just a few meters. We don't even know the exact location of GPS satellites orbiting Earth within a few meters. So I would imagine that it's well within the range of measuring error for the Pioneer spacecraft. —Preceding unsigned comment added by 69.244.30.43 ( talk) 18:37, 14 October 2007 (UTC)
![]() | This page is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Should this be added to the page?
Exotic cause of 'Pioneer anomaly' in doubt
I'd do it, but I can't be bothered to absorb the entire page well enough to put this in the right place. :)
—
Aristotle
11:48, 22 June 2007 (UTC)
This used to be on the page, though in a paper by Iorio rather than the paper referenced in the article (though they have exactly the same conclusion). I checked and it was removed by an anonymous editor 63.130.192.57 on 25 May, while also removing some more dubious stuff. I've re-added it to the possibility of gravitational causes. LouScheffer 15:33, 22 June 2007 (UTC)
According to Alan Stern, prime investigator of New Horizons space probe (former Pluto-Kuiper Express), this probe will be spin-stabilized during cruise and thus his radio team is hoping to look for the Pioneer Anomaly in their data. -- Mandevil 09:15, 24 Feb 2005 (UTC)
' As far as i have heard, the radiation pressure from the rtg should mask the 'anomaly' for new horizons. nevertheless, people might try to use the REX instrument (which is basically a radio transmission expreriment as a "probe") and to compute precisely the thermal radiation pressure.
a recent reference for that : New Horizons and the Onset of the Pioneer Anomaly, Michael Martin Nieto http://arxiv.org/abs/0710.5135v1
OK, added this to the article. -- LouScheffer ( talk) 21:16, 16 November 2007 (UTC)
I just wonder have the scientists accounted for Sol gravitational well when estimating the drift? What i mean is that electromagnetic wave increase/decrease in frequency when escaping/incoming the gravity center
one more thing to be careful about is the speed of the pioneer - how big the relativistic effects are at that speed (time dilation) - have this effect been accounted for?
one more question - "The drift can be interpreted as due to a constant acceleration of (8.74 ± 1.33) × 10−10 m/s2 directed towards the Sun." could this be caused by the masses of all the planets and asteroids in the solar system (especialy the Jupiter) ?
Regarding your questions: yes, the gravitational Doppler effect has been accounted for in the calculations, and introduces a negligible correction which cannot explain the anomaly. This is a standard procedure in telemetry and Doppler analysis of any spacecraft.
Also, the crafts are travelling at a speed that is many order of magnitudes lower than the speed of light, so that time dilation cannot account for the effect. Furthermore, since the effect reveals itself through the unexplained Doppler shift, the relevant relativistic correction is the aforementioned gravitational Doppler effect.
Finally: although the numbers don't match, it could be possible that, at a certain time and position throughtout its voyage, the probes were subject to a gravitational pull from Jupiter and other bodies that equals the anomaly. However, the key word here is "constant acceleration": all gravitational forces decrease with the inverse of the distance squared, so it appears impossible to describe a constant effect through it. And, of course, all known gravitational effects were previously accounted: NASA engineers do mean business (Anderson et. al.)!
A slightly more convoluted discussion involves the gravitational force due to objects in the Kuiper belt. It has been shown (Bertolami and Vieira) that only a exceedingly odd density profile for these objects could approximate the effect, and even so only within a narrow region of space.
Hope I was of some help.
Jorge
Thomas your page has one additional piece of information, that the beam of the antenna is not wide enough to deduce anything but a earth directed acceleration, if that is true the story is possibly a hoax , as it tends to digress to sun-pointing accelleration instead. Anyway i can imagine gravitational drags or magnetic shifts of some influence, I would also not be surprised if it was the shadow of the antenna. perhaps the relevance of the earth magnetic field naturally gets more pronounced on certain trajectorys but i would think that had very limited windows.(1g per au is suggestive) I don't know in how far metal molds correspond to the overall earth magnetic field(not to bad i think) and i can't imagine it would matter this much(the flyby effect seems the effect of earth magnetic (gravitational) variation but i dont know if that could induce that variety, i would think yes since the effect is small and the earth is big, perhaps eg. it matters if the part you fly over is warm). 77.248.56.242 23:34, 13 June 2007 (UTC)
The wrong sign? Please explain
"The pressure of sunlight is too small at this distance, and the wrong sign, as are the spacecraft's radio emissions"
You mean, "and is on the wrong side"?? -- 129.139.18.18 18:54, 9 April 2007 (UTC)
I removed today (April, 18, 2007) the likely self-promoting external link to [1], compilation of JPEG files of non-peer-reviewed scanned manuscripted work (see the historic to see when and how it had been added, November 2006). Nevertheless, I have no clue in physics, so it would be useful that anyone a bit more aware than I am have a look at his page and see if the link needs be added once more.
Someone took issue with my addition of a link to Alexander Mayer's The Many Directions of Time, so I thought I'd expand on it a little here. First, I have absolutely no connection with Mayer other than having read his work. Yes, it is a self-published ebook. However, the transverse gravitational redshift theory is firmly grounded in general relativity and makes many empirically testable predictions. This is the hallmark of a good scientific hypothesis. If this was obvious quackery such as Time Cube removing it would be justified, but that's not the case here. Whether Mayer is right or wrong, removing a reference to a possible explanation because you don't like the web page is, in my opinion, a disservice to Wikipedia readers.
I'll try to address each of your points.
In summary, I have no idea if Mayer is right. He may well be wrong. But I find his claims and supporting data compelling enough to warrant some investigation. Given the plethora of empirically testable predictions made in the book, some enterprising experimentalists ought to be able to discover whether or not Mayer is on to something - but for that to happen, they have to at least be aware of the theories, hence my motivation for making the information available. The list we are editing is called "Possible explanations", not "Ironclad explanations" and all of the new physics portion involves controversial modifications to current theories. I don't see why Mayer is any different in that regard. I'll say one thing - he seems to be doing a heck of a lot better than the superstring theorists at making testable predictions.
The case you are talking about (two clocks each perceived as running more slowly than the other) is extremely common within Einsteinian special relativity - that's how relativistic time dilation works. If one observer is moving at high speed relative to another and each are transmitting clock data, they will perceive each other's clocks as being slower than theirs. Do you also assert that special relativity is wrong? I think the problem with your scenario is that you are making the assumption that there really is a consistent universal time axis that you can measure against, which is just not the case for Mayer's geometric time or for relativistic time dilation. It defies common sense, but each observer really will have different tick counts because the perceived frequencies of each clock is not the same. In fact, if you read Mayer's work you find that the whole concept of geometric time is rooted within special relativity, much as TGR is rooted in general relativity. Pheran 15:39, 28 June 2007 (UTC)
Dear editors, the data provided below was added earlier into the article, in the related section, but then removed with the comment "ESA ref does not mention pioneer, second ref is another self-published TOE by a non-scientist". Well, although the ESA link, 2006, does not mention the pioneer anomaly it does demonstrate the possible deviations from Einstein-Newtonian law of gravitation that Kunst's paper already in 1999 refers as being measured in laboratory and at astronomical scale; the second ref as you may very well deduce, and as it is known by several "relativity" editors around, it is a 2002 paper from a scientist with a highly reputable background, yet a taboo among the academic physics community (ask yourselves why!):
Obviously, from my past editing experiences here at Wikipedia there seems to be many individuals around not interested that the lay public becomes acquainted with these other perspectives within the scientific community. Friendly. —The preceding unsigned comment was added by 213.58.99.92 ( talk • contribs) 23:17, 23 July 2007 (UTC).
In line with WP:BOLD, I am removing a pile of external links that I think are better not in the article. If someone, after double checking relevant wikipedia guidelines, feels that some of these should be restored, do please feel free to revert individual links as you see fit. If this occurs, I will not revert back. I may tag the link, and engage discussion here.
Here are links I have removed.
These are the links that remain.
— Duae Quartunciae ( talk · cont) 22:17, 29 July 2007 (UTC)
Maybe I did the math wrong, but a force of (8.74 ± 1.33) × 10^−10 m/s2 across 35 years (1.10449241 × 10^9 seconds) works out to just a few meters. We don't even know the exact location of GPS satellites orbiting Earth within a few meters. So I would imagine that it's well within the range of measuring error for the Pioneer spacecraft. —Preceding unsigned comment added by 69.244.30.43 ( talk) 18:37, 14 October 2007 (UTC)