Question
Sun March 04, 2012 By:
 

if stars are light years away from earth then how does their light reach us ?

Expert Reply
Sun March 04, 2012
The nearest star to us is the Sun and it takes about 8.3 minutes for its light to reach us here on Earth. The next closest star to us is Proxima Centauri. This star is 4.3 light years away which means that light from it takes 4.3 years to reach us. Our galaxy is about 100,000 light years across. This means that it can take tens of thousands of years for light from some stars in our galaxy to reach us. For stars that we can see in nearby galaxies it can take millions of years. The farthest objects we can see are quasars. They are so distant that the light we see from them today left billions of years ago.
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