Why does the space appear black to the astronauts.

Dear Student

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. 

Space has no atmosphere and thus nothing for the light to become "scattered" on, and so no colors for you to see.

NOTE: even though universe is full of stars, it appears black. This is explained as: that the universe is not infinitely old; it is somewhere around 15 billion years old. That means we can only see objects as far away as the distance light can travel in 15 billion years. The light from stars farther away than that has not yet had time to reach us and so can't contribute to making the sky bright

 

 Hope that satisfies your query.

 

Team

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