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I am trying to find an outside source say Mars may get swallowed up by sun in 6-7 billion years [1] I can't remember every source I visited in the history stating Mars may even get eaten up by sun. Is the best answer to state Mars will definitely not get eaten by sun in 6-7 billion years or best answer is since Mars is further away from sun than Earth is it stands at better chance surviving than Earth? I don't know who said sun's expansion can reach 2 AU. Maybe our diagram is somebody made mistake, because I can't find other source said 2 AU? I am guessing somebody on Wikipedia made mistake-- 69.233.254.115 ( talk) 02:04, 2 July 2013 (UTC)
Is there somewhere that will tell me what the other objects in this file are? I just have a curiosity about what the big blue object is to the lower left of Andromeda is or what the wide yellow object is in the lower center of the image. Once I was curious about those, I looked more and kept asking "I wonder what that is too!" about various other points of light. So, maybe if there was a site where I could click and zoom around from the Earth's point of view, that would answer all my questions. Is there such a site? Thanks, Dismas| (talk) 05:00, 2 July 2013 (UTC)
Thanks for the links, everyone. I tried Google Sky but it doesn't name every, or even most, object(s). Dismas| (talk) 23:56, 2 July 2013 (UTC)
hey people I have got into institute if chemical technology for btech oils for first year engineering. wats d opportunity for campus placements? nd does it make a gud branch? — Preceding unsigned comment added by 59.183.34.74 ( talk • contribs) Looie496 ( talk) 06:41, 2 July 2013 (UTC)
...and I'd be too embarrassed to tell you what it is. Fortunately, I know from experience it'll be a different song tomorrow. But seriously, it seems it happens to a lot of us. Has any serious research been done on it? How much of the population does it happen to? Does it vary between cultural groups? I sometimes wake up with a song going round in my head that I haven't heard or thought about in years. Is that common? What's really going on with this? HiLo48 ( talk) 07:42, 2 July 2013 (UTC)
Hi I've been listening to a few lectures and debates by Professor Lawrence Krauss and find him a fascinating and progressive champion of science. Is he highly regarded as a scientist (possible Nobel material) or does he fall into the category of celebrity scientists? In more than one of his lectures, he mentioned that ordinary matter comprises only 1% of the universe with everything else comprised of about 30% dark matter and about 70% dark energy. He proudly calls us cosmic pollution and says repeatedly that we are more insignificant than we think! Now, the dark matter article disagrees and says that ordinary matter is 4.9%. Who is correct? Is there more than one school of thought in how the mass-energy of the universe is measured? Sandman30s ( talk) 07:51, 2 July 2013 (UTC)
Do we have somewhere a list of people ordered by the number of citations they draw (I mean "cites" that other people use when writing articles / books)? I am wondering if anyone keeps counts, at least for the ~10 most respected scientific publications (but to be honest I would be interested in any study provided they explain what counts and what doesn't. -- Lgriot ( talk) 08:50, 2 July 2013 (UTC)
Charles Murray's Human Accomplishment addresses this topic on a worldwide basis, giving statistics for work done up to 1950. I am fairly certain Newton comes in first place. μηδείς ( talk) 22:05, 2 July 2013 (UTC)
There's been discussion of dark matter around here for some time [2] ; meanwhile, more "dark matter galaxies" are being announced or suspected: [3] [4]
Now, I understand there are many models of dark matter which represent it as hot, fast-moving, even non-self-interacting, so that it doesn't form physical "chunks". Still, I thought I should ask: how much can we currently restrict that model based on what has been observed? I assume we can't absolutely rule it out (assuming more than one kind of dark matter may exist) but we could limit the amount that is possible?
In other words, I suppose if you had a "dark matter planet" that went through or even near the Earth, we'd really find out about it due to tidal effects. If a "dark matter asteroid" is possible it would presumably make anomalies in satellite motion. And "dark matter stars" ought to leave other suns circling without a visible reason. I assume someone has looked for the limits of such evidences?
A particular scenario that appeals to me is a supernova remnant, which is often asymmetrical, shooting a remnant off into space at high speed. Presumably any dark matter that it gobbled up during life should remain gravitationally bound at the point of origin, right? So... does anything turn out to be perturbing the gas remaining at that point? Wnt ( talk) 15:35, 2 July 2013 (UTC)
Any ideas? Just a question that occurred to me when eating one of those super-sour Toxic Waste sweets recently. I do seem to recall that something was once announced as the most foul-smelling object in the known universe... -- Kurt Shaped Box ( talk) 20:53, 2 July 2013 (UTC)
One should take care that one is dealing with the correct concept. "Sourness" might relate to hydronium concentration rather than proton donation. — Quondum 03:03, 3 July 2013 (UTC)
When we analize the interaction between two current carying conductors we first represent the magnetic induction "B" following the right hand rule. But, if you look back at the origine of this representation you can find that it comes from Faraday and the orientation of the magnetic induction "B" was based on the pattern of iron filings formed around a magnet bar which resemble to " field of lines" conneting the two poles. If you look closer the iron piling particles also can be considered tini magnets and their orientation will always be that their internal atomic currents that creates their magnetic field will be aligned with the internal atomic currents of the large permanent magnet bar so they will tend to have the same direction ! The independent "lines" are formed because the adjacent particles of iron will align their internal currents with the stronger current of the large permanent magnet bar while between the "lines" there will be repulsion, also particle of iron from a "line" will form chains with the top and the bottom particle so that their internal currents will be aligned too. So now from the two parallel electric current situation we arrive to another two parallel electric current situation! And the real magnetic field looks more like "something" that is allong the lenght of the conductor. Think about two ships on water that moves parallel to each other in the same direction. Because of Bernoulli effect the ships will be drawn together, but if they move in opposite directions they will be pushed away from each other...The same it seems to be with the magnetic field too. There is no such a thing like magnetic induction "B" that is tangent to the conductors or circle the conductor...its just an illusion ! Can you see the error? — Preceding unsigned comment added by 71.185.132.57 ( talk • contribs)
I think that you are confusing "magnetic induction B" which is also called "magnetic field" (read wikipedia :) with "electromagnetic induction" ... Saying that " magnetism obeys simple rules" its a very superficial statement, anyway.
Science desk | ||
---|---|---|
< July 1 | << Jun | July | Aug >> | July 3 > |
Welcome to the Wikipedia Science Reference Desk Archives |
---|
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages. |
I am trying to find an outside source say Mars may get swallowed up by sun in 6-7 billion years [1] I can't remember every source I visited in the history stating Mars may even get eaten up by sun. Is the best answer to state Mars will definitely not get eaten by sun in 6-7 billion years or best answer is since Mars is further away from sun than Earth is it stands at better chance surviving than Earth? I don't know who said sun's expansion can reach 2 AU. Maybe our diagram is somebody made mistake, because I can't find other source said 2 AU? I am guessing somebody on Wikipedia made mistake-- 69.233.254.115 ( talk) 02:04, 2 July 2013 (UTC)
Is there somewhere that will tell me what the other objects in this file are? I just have a curiosity about what the big blue object is to the lower left of Andromeda is or what the wide yellow object is in the lower center of the image. Once I was curious about those, I looked more and kept asking "I wonder what that is too!" about various other points of light. So, maybe if there was a site where I could click and zoom around from the Earth's point of view, that would answer all my questions. Is there such a site? Thanks, Dismas| (talk) 05:00, 2 July 2013 (UTC)
Thanks for the links, everyone. I tried Google Sky but it doesn't name every, or even most, object(s). Dismas| (talk) 23:56, 2 July 2013 (UTC)
hey people I have got into institute if chemical technology for btech oils for first year engineering. wats d opportunity for campus placements? nd does it make a gud branch? — Preceding unsigned comment added by 59.183.34.74 ( talk • contribs) Looie496 ( talk) 06:41, 2 July 2013 (UTC)
...and I'd be too embarrassed to tell you what it is. Fortunately, I know from experience it'll be a different song tomorrow. But seriously, it seems it happens to a lot of us. Has any serious research been done on it? How much of the population does it happen to? Does it vary between cultural groups? I sometimes wake up with a song going round in my head that I haven't heard or thought about in years. Is that common? What's really going on with this? HiLo48 ( talk) 07:42, 2 July 2013 (UTC)
Hi I've been listening to a few lectures and debates by Professor Lawrence Krauss and find him a fascinating and progressive champion of science. Is he highly regarded as a scientist (possible Nobel material) or does he fall into the category of celebrity scientists? In more than one of his lectures, he mentioned that ordinary matter comprises only 1% of the universe with everything else comprised of about 30% dark matter and about 70% dark energy. He proudly calls us cosmic pollution and says repeatedly that we are more insignificant than we think! Now, the dark matter article disagrees and says that ordinary matter is 4.9%. Who is correct? Is there more than one school of thought in how the mass-energy of the universe is measured? Sandman30s ( talk) 07:51, 2 July 2013 (UTC)
Do we have somewhere a list of people ordered by the number of citations they draw (I mean "cites" that other people use when writing articles / books)? I am wondering if anyone keeps counts, at least for the ~10 most respected scientific publications (but to be honest I would be interested in any study provided they explain what counts and what doesn't. -- Lgriot ( talk) 08:50, 2 July 2013 (UTC)
Charles Murray's Human Accomplishment addresses this topic on a worldwide basis, giving statistics for work done up to 1950. I am fairly certain Newton comes in first place. μηδείς ( talk) 22:05, 2 July 2013 (UTC)
There's been discussion of dark matter around here for some time [2] ; meanwhile, more "dark matter galaxies" are being announced or suspected: [3] [4]
Now, I understand there are many models of dark matter which represent it as hot, fast-moving, even non-self-interacting, so that it doesn't form physical "chunks". Still, I thought I should ask: how much can we currently restrict that model based on what has been observed? I assume we can't absolutely rule it out (assuming more than one kind of dark matter may exist) but we could limit the amount that is possible?
In other words, I suppose if you had a "dark matter planet" that went through or even near the Earth, we'd really find out about it due to tidal effects. If a "dark matter asteroid" is possible it would presumably make anomalies in satellite motion. And "dark matter stars" ought to leave other suns circling without a visible reason. I assume someone has looked for the limits of such evidences?
A particular scenario that appeals to me is a supernova remnant, which is often asymmetrical, shooting a remnant off into space at high speed. Presumably any dark matter that it gobbled up during life should remain gravitationally bound at the point of origin, right? So... does anything turn out to be perturbing the gas remaining at that point? Wnt ( talk) 15:35, 2 July 2013 (UTC)
Any ideas? Just a question that occurred to me when eating one of those super-sour Toxic Waste sweets recently. I do seem to recall that something was once announced as the most foul-smelling object in the known universe... -- Kurt Shaped Box ( talk) 20:53, 2 July 2013 (UTC)
One should take care that one is dealing with the correct concept. "Sourness" might relate to hydronium concentration rather than proton donation. — Quondum 03:03, 3 July 2013 (UTC)
When we analize the interaction between two current carying conductors we first represent the magnetic induction "B" following the right hand rule. But, if you look back at the origine of this representation you can find that it comes from Faraday and the orientation of the magnetic induction "B" was based on the pattern of iron filings formed around a magnet bar which resemble to " field of lines" conneting the two poles. If you look closer the iron piling particles also can be considered tini magnets and their orientation will always be that their internal atomic currents that creates their magnetic field will be aligned with the internal atomic currents of the large permanent magnet bar so they will tend to have the same direction ! The independent "lines" are formed because the adjacent particles of iron will align their internal currents with the stronger current of the large permanent magnet bar while between the "lines" there will be repulsion, also particle of iron from a "line" will form chains with the top and the bottom particle so that their internal currents will be aligned too. So now from the two parallel electric current situation we arrive to another two parallel electric current situation! And the real magnetic field looks more like "something" that is allong the lenght of the conductor. Think about two ships on water that moves parallel to each other in the same direction. Because of Bernoulli effect the ships will be drawn together, but if they move in opposite directions they will be pushed away from each other...The same it seems to be with the magnetic field too. There is no such a thing like magnetic induction "B" that is tangent to the conductors or circle the conductor...its just an illusion ! Can you see the error? — Preceding unsigned comment added by 71.185.132.57 ( talk • contribs)
I think that you are confusing "magnetic induction B" which is also called "magnetic field" (read wikipedia :) with "electromagnetic induction" ... Saying that " magnetism obeys simple rules" its a very superficial statement, anyway.