On Wed, Nov 19, 2008 at 10:05:56PM +0530, Venkat Mangudi wrote: > So we are the reason that the earth is habitable? I thought the planet
We're the best chance future Earth ecosystem has. (And the greatest threat, of course. Pick your poison). > went through cycles of cooling and heating and we are stuck in one of > them. Guess I need to read more. Interesting to note that earth will The Sun is only 4.6 gigayears old. It has been becoming 10% more luminous each gigayear. I've seen estimates that after next 0.5 Ga the surface is unfit for higher life. See http://en.wikipedia.org/wiki/Sun#cite_note-Schroeder-31 and http://en.wikipedia.org/wiki/Sun#cite_note-32 If we screw up real good, there won't be a chance for another intelligent species, should one evolve by some crazy chance. > become another Mars if all humans die. What's the name for those who Huh? Mars will be much warmer when solar constant is up. Not that it will be any help with surface volatiles, given it's lack of geodynamo to protect from solar wind ablation. But, surface temperatures will be rather balmy, even as surface pressure will be likely much less than today's 6 mbar. > think that the Universe (or the multiverse, on second thoughts do they > think there is a multiverse?) exists primarily for us humans? I do not subscribe to the purpose of intelligence as universe's creation boundary condition. The universe's purpose is whatever you make it.
