October 19th, 2008
Episode 119 of 478 episodes
Another week, another roundup of your questions. This week listeners asked: what is galactic dust anyway, and where does it come from? Why can photons move at the speed of light? And how can astronomers know what happened right after the Big Bang? And there's even more. If you've got a question for the Astronomy Cast team, please email it in to [email protected] and we'll try to tackle it for a future show. Please include your location and a way to pronounce your name.