Oceanographer John Delaney Jumps in Europa's Ocean

He has visited the ocean floor, and directs the exciting new Neptune project, but oceanographer John Delaney also makes time to wonder about the ocean under the ice of Jupiter's moon Europa. He talks about why research here will help us explore there on this week's show. Emily Lakdawalla can tell a comet from an asteroid, and Bruce Betts knows What's Up and says name that spot in this week's trivia contest.