The Sky at Night S2010E03 - Life

Half a century ago, scientists were speculating about the possibility of planets outside our solar system. Since then over 400 such extra-solar planets have been discovered. Is there anything living on them and if so, is it intelligent? Sir Patrick Moore debates the question of life in the universe with today's planet hunters and astrobiologists, while at the Royal Society Dr Chris Lintott searches for evidence of alien life.