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When we see a star in the night sky, we are actually seeing how it was sometime in the past. This is because light takes time to travel from the star to Earth. Light travels 9.5 × 1015 m in one year. This distance is called 1 light year. When an astronomer sees the star Betelgeuse, which is approximately 6.08 × 1018 m from Earth, how long ago did the star appear the way it does to her today?