Astronomy Cast Ep. 610: What is Required to Confirm Alien Life: Non-Sentient Edition by Fraser Cain & Dr. Pamela Gay Are we alone in the Universe? It's one of the biggest scientific questions we can possibly ask. And yet, with rovers on Mars, missions planned to visit Europa and Ganymede. Powerful telescopes able to detect the atmospheres of exoplanets, we're closer than ever to finding out the answer.