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How far are stars from Earth?
Question Date: 2006-01-13
Answer 1:

Our sun is the nearest star to Earth. After the sun, the next nearest star is 4.3 light years away. A light year is the distance light travels in one year. One light year is 10 trillion kilometers. That's a HUGE number! Here's a way to imagine how far it is: to travel 10 trillion kilometers, you would have to circle the whole Earth 233 million times.

Answer 2:

Distances to stars are usually quoted in "light years" which is the distance that light travels in one year. Light travels 300,000 kilometers per second or 186,000 miles per second so light travels very far in one year - 9.5 X 1015 meters. The closest stars are about four light years away and there are several stars that are less than 20 light years away.

Our galaxy is about 80,000 light years wide so stars still in our galaxy can be thousands of light years away.

By the way, the star closest to the Earth is, of course, the Sun which is about 93 million miles away or 500 light seconds.

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