Mars Exploration Rover Program Manager John Callas

29 min • 19 november 2007

John Callas provides a status report on Spirit and Opportunity. Emily Lakdawalla is looking at brilliant Comet Holmes in her Q&A report, and Bruce Betts also makes room for Holmes in his What's Up! review of the night sky.Learn more about your ad choices. Visit megaphone.fm/adchoices