How Stuff Works  |  Podcast, ±2 min episodes every 2 days
Join Marshall Brain in the BrainStuff Podcast and learn answers to life's everyday questions. Improve your knowledge with the BrainStuff Podcast.
A light year is a way of measuring distance -- specifically, the distance light can travel in one year. Just how far is that? Check out this classic Brainstuff podcast from HowStuffWorks' archives to learn more about astronomy.