Planetary Radio 5th Anniversary Show: Astronomer Geoff Marcy on Discovery of Fifth Planet in Star System

Five planets circling another star help us celebrate the fifth anniversary of the show. UC Berkeley's Geoff Marcy, leader of the exoplanet discovery team, tells us about the growing solar system at 55 Cancri. Emily Lakdawalla wonders why Jupiter's Great Red Spot is red, but she knows the Jovian storm has evolved over the years. Bruce Betts and Mat Kaplan award fifth anniversary prizes.