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à=Ð/Ð8What is a Light Year?
The distances between stars are vast on our scale of things. Using a normal unit such as a
mile or a kilometer would be too cumbersome because of all the zeros required. As a
result, astronomers use the fastest thing in nature, light, to provide the unit of distance
between stars. It is called the “light year” and is not a measure of time but of distance. It
is the distance that light travels in one year. Light travels about 186,000 miles per second.
Doing the calculations, one light year is equal to about 5.9 trillion miles. The nearest star,
Proxima Centauri, is 4.27 light years away, or around 25 trillion miles.
planets remaining, most of these have probably never experienced life (although if Mars
did have life, the odds increas‰{‰‰‰
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