Spike Jones wrote:
> Is there a way to calculate an upper bound on the density
> of dust between stars?
>Wait, I think I can upper bound the density knowing that
>there is no more than 10 times the amount of matter in the
>universe than is visible in the stars. Otherwise the universe
>would be obviously closed. Right?
Dooooh! Somebody save me from myself. This upper
bound would require 90% of the matter in the universe
to be not-hydrogen-or-helium, which is absurd by any
model Ive heard proposed. I think I recall a good
argument that the upper bound on the fraction of
metals in the current epoch is about 1% the mass of
the hydrogen and helium. So that puts an upper bound
of about 200 nanograms of interstellarlopers per cubic
kilometer. Right? Amara? spike
This archive was generated by hypermail 2b30 : Mon May 28 2001 - 09:50:35 MDT