Astronomer Phil Plait is one of three guests invited on MSNBC science editor Alan Doyle’s online talk show. They talk about the recent discovery of two Earth-sized ‘exo-planets’ and what it means for our search for life on other planets: http://cosmiclog.msnbc.msn.com/_news/2011/12/20/9591482-quintet-gangs-up-on-alien-worlds
