water on mars... again...
Posted: Fri Sep 25, 2009 9:21 am
APOD and General Astronomy Discussion Forum
https://asterisk.apod.com/
http://en.wikipedia.org/wiki/Fimbulwinter wrote:
<<In [Viking] mythology, Fimbulvetr (or fimbulvinter) is the immediate prelude to the events of Ragnarök. Fimbulvetr is three successive winters where snow comes in from all directions, without any intervening summer. During this time, there will be innumerable wars and brothers will kill brothers.
The prefix 'fimbul' means "the great/big" so the correct interpretation of the word is "the great winter".
There have been several popular speculations about whether this particular piece of mythology has a connection to the climate change that occurred in the Nordic countries at the end of the Nordic Bronze Age, about 650 BC. Before this climate change, the Nordic countries were considerably warmer.>>
I believe that hydrogen is the most abundant material in the universe, followed by helium. Even if you were talking molecular substances, I believe that molecular hydrogen is far more abundant than water. However, water, as a simple molecule, is probably relatively common, as are ammonia and methane.northstar wrote: "Water water everywhere .... " I've read that water is the most common substance in the universe.
Good article on water in the universe. http://en.wikipedia.org/wiki/Water#Wate ... e_universebystander wrote:I believe that hydrogen is the most abundant material in the universe, followed by helium. Even if you were talking molecular substances, I believe that molecular hydrogen is far more abundant than water. However, water, as a simple molecule, is probably relatively common, as are ammonia and methane.northstar wrote: "Water water everywhere .... " I've read that water is the most common substance in the universe.
I think the term abundance is relative. Certainly on habitable planets, water is abundant, probably much more abundant than hydrogen. However, on gas giants, hydrogen and helium dominate, and concentrations of ammonia and methane are higher than water. In molecular clouds, and the universe as a whole, I suspect the concentrations are skewed even more in the direction of the lighter molecules and atoms.northstar wrote:Good article on water in the universe. http://en.wikipedia.org/wiki/Water#Wate ... e_universe
But, the gasses on Jupiter and Saturn are not liquid. How would their volumes compare to water on earth if they were liquified?bystander wrote:
You have to admit that the predominance of hydrogen and helium on those 5 most massive objects in the solar system far out weighs the presence of water on any of the other planets and moons, including Earth.
Considering that Jupiter is 2.5 times the mass of all the other planets in our Solar System combined, I would still say that water on Earth is negligible.northstar wrote:But, the gasses on Jupiter and Saturn and not liquid. How would their volumes compare to water on earth if they were liquified?
I understand that recent speculation suggests strongly that Jupiter and Saturn have massive, rocky cores.bystander wrote:Considering that Jupiter is 2.5 times the mass of all the other planets in our Solar System combined, I would still say that water on Earth is negligible.northstar wrote:But, the gasses on Jupiter and Saturn and not liquid. How would their volumes compare to water on earth if they were liquified?
and another great youtube short ft carl saganmakc wrote:p.s. unrelated