Phil Plait is the guy I call whenever something cosmic goes down, such as this weekend’s return of the Stardust mission after a nearly three-billion-mile roundtrip to bring pieces of a comet back to earth. On my show, Phil explained what that means, what NASA did, and why we should care. Listen, then click here to subscribe to these podcasts via iTunes!

Phil first became known to my audience several years ago when he debunked the nonsense about the moon landing being a hoax, and has returned to discuss other space-related topics. As his Bad Astronomy blog proves, he’s very good at putting complex concepts into easily understood terms for non-scientists like you and me.