Light Year- A light year is the measure of distance which describes the amount of distance travelled by light in a vacuum during 1 Earth Year. It's a little misleading because the name can be easily misunderstood to mean an amount of time. A light year is a vast amount of distance. Light travels 300,000,000 m/s, or 3 million km in on second. It takes roughly 8 minutes for light to travel from the sun to the Earth. New Horizons just travelled all the way to Pluto, roughly 7 billion miles. This immense distance represents roughly .0007 light years. The nearest star, except our Sun is something like 4 Light Years. A light year is a very long distance, but it can be very useful when measuring large distances and exploring our Cosmos.
