How the Universe Works (2010)

S3E9 The Search for a Second Earth

Could there be another Earth somewhere in the universe, complete with liquid oceans, solid landmasses, and life as we know it? Astronomers are on a quest to uncover this mystery using techniques such as spectroscopy, direct imaging, and advanced telescopes. Their goal is to discover indications of atmospheres, magnetospheres, and potential signs of extraterrestrial life.