Short Lesson on Meaning of Light Years

FOOD FOR THOUGHT: I am currently looking at Orion's Belt from my house right on the beach and due to the Turtle Law, all lights must be out. As a result, the stars are very noticeable. Apparently, this particular group of stars is 900 light years away. What that means is, that it takes us 900 years to see the light from these stars that we happen to be viewing right now, and vise verse. With that said, if there was some being living in a planet or other body near that star and they had a telescope to see what the earth looked like, they would be watching crazy battles during the Medieval period in Europe (William the Conqueror killing it!). They would see the start of the first crusade, the game of checkers invented, the Pueblo Indians in the southwest of North America were just getting started, and the city of Cusco, Peru being founded (all occurring around the year 1000 AD). Incredible!