Mankind took another giant step in outer space today. A 220-pound lander that's about the size of a washing machine touched down on a comet 300-million miles from earth. The comet is just two-and-a-half miles wide and this accomplishment has been compared to catching a bullet. Anderson spoke to CNN Aviation Analyst Miles O'Brien and Bill Nye 'The Science Guy' about the more than ten years of planning that went into today's landing.