Question

why do the astronaut see the sky as black???
anyone can answer that one.........
let me know...

Answer 1

the sky is black instead of blue to astronauts because there is nothing to bounce color back to their retina

Answer 2

in space outside the atmosphere of earth, there is no scattering of the sun's blue part of the spectrum's light. I am not sure what particles of the atmosphere cause scattering, nitrogen or oxygen, but that is the principle. Also the reason that the sun is redish to yellow for us, and bright white for astronauts. So for them light is more black/white than for us.

Answer 3

see: http://en.wikipedia.org/wiki/Black#Color_or_light_in_science

Answer 4

or http://en.wikipedia.org/wiki/Scattering