What is a light-year? Physics definitions

By |2018-05-31T11:49:14-07:00August 16th, 2017|Physics|

Light takes years to reach us from these stars far away in space. A light-year is the distance that light can travel in one year - that is, in the time it takes the planet Earth to make one full trip around the Sun. Light travels 186,000 miles in a second, so in [...]