Question
Thu February 02, 2012 By: Shabad Lamba
i know that due to atmossphere present in Earth white rays of sun after scattering appears blue, thus sky appears blue .

When there is no atmosphere in the space then why does space appears black instead of white?

Expert Reply
Thu February 02, 2012
The daytime sky is blue because light from the nearby Sun hits molecules in the Earth's atmosphere and scatters off in all directions. The blue color of the sky is a result of this scattering process. At night, when that part of Earth is facing away from the Sun, space looks black because there is no nearby bright source of light, like the Sun, to be scattered. If you were on the Moon, which has no atmosphere, the sky would be black both night and day. You can see this in photographs.
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