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comment What causes the aurora of other planets to have different colors?
'Different' You can look that up with 0 work. Gas giant atmospheres are dominated by $H_2$. It's the $H_2$ bands that radiate in the UV when excited by elctron precipitation. They don't radiate in the optical as the hydrogen molecule doesn't have allowed lines there.
Aug
21
comment Meteors made of differing substances. Will they all burn up?
Downvote. Speed of collisions has nothing to do with burnup. Shock velocity due to high mach number, however has.
Aug
12
comment Configuration required to tidally heat Earth-like rogue planet
userLTK: Then ofc there would be the question if this configuration is stable over Gyrs, what I guess OP's question aims at. Tidal heat in the end is converted orbital angular momentum.
Aug
7
comment Why are so many sun-like stars found in multiple systems? How do planets form in such a situation?
50% of all stars are binaries. We do not know how many planets in general those host. We only have an idea about Single G stars, some single G and M (upcoming with Kepler2) and only in a certain mass and radius range. It therefore may take still several decades to answer your question.
Aug
2
comment What is space temperature around Earth?
@Anixx: Because any physical (non-ideal) black-body will have a finite reflectance that plays a decisive role in how much energy it finally recieves and can absorb.
Jul
8
comment How to tell a crater is old or not?
This only gives relative age, but no Idea about absolute age. To get this you have to actually go there and get samples.
Jul
2
answered Accidental or deliberate?
Jun
10
comment For how many bodies can there be a stable orbit with no very heavy central body?
Stability would need a mathematical proof, which we can already do for the 3-body-problem only in special cases. For arbitrary N-body that's impossible.
Apr
12
comment Is the sun too small to self-ignite?
One could add maybe the mention of the Gamow Peak, nu.phys.laurentian.ca/~fleurot/fusionrate which quantifies the statements made above. Also Deuterium burning already happens in Giant Planets / Brown dwarves that are less massive than the sun.
Mar
28
comment How can you determine the initial volume of a planet's atmosphere?
Also if you want a initial atmosphere, its link with the protosolar nebula is continuous, maybe separated by an accretion shock onto the planet. There you could define the volume, but in later eras it doesn't make sense to talk about the volume. @td-lambda: Why are you interested in that? If you're really about initial conditions then why not rather define surface pressure and temperature?
Mar
27
comment How did water get on Earth
@pela: I think we can leave it be, as a little discussion is sometimes illuminating, as in this case too.
Mar
27
answered How did water get on Earth
Mar
27
comment How did water get on Earth
This number of 1/6 you're citing is only valid if the whole atmosphere has the temperature. In case of a hot plume of this temperature launched in the troposphere, this will be easily trapped in the lower atmosphere, and can maybe wirl up dust higher up, like we know it from volcanic eruptions. However like @Rob-Jeffries said, it's important how fast the plume cools.
Mar
26
answered Do we still use the term “astronomical unit” nowadays?
Mar
24
comment Dynamic Method-Please explain
Do you mean perturbations of heavier objects (e.e. gas giants) that have known masses?
Mar
19
comment Why did Venus not lose its atmosphere without magnetic field?
@MacUserT: Mars' atmosphere has the same 'heavy gasses' as Venus does - $CO_2$ up to a dominant degree. Therefore the atmospheric composition cannot make the difference, as there is none.
Mar
10
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Feb
17
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Feb
11
comment What astronomical observations would give conclusive proof of alien life?
Hot topic perhaps, but certainly one of the least scientificly conducted ones.
Feb
7
comment How do moons get captured?
But usually you simply need another fourth body, or a mass of bodies, that number 3 can throw out to loose angular momentum. This at least is alot more probable/efficient in a your solar system, than the mentioned mechanisms.