Are we alone?  This question has inspired scientific research for millenia, but in the last fifty years astronomers have taken the first tentative steps toward answering it.  In this planetarium show, we journey to the worlds of our Solar System, from Mars to Saturn’s moons Enceladus and Titan, in search of environments that could potentially foster life.  We then travel hundreds of light-years away from the Sun to explore some of the most extreme, most bizarre and most Earth-like extrasolar planets discovered to date.