Bad news, fellow denizens of Earth: According to some new astrobiological research, our home planet will not be habitable for much longer. As our Sun gets older, it will get larger and warmer, eventually leading to the Earth becoming uninhabitable -- first to humans and other complex life, and then, in around 1.75 to 3.25 billion years, to all cellular life as we know it. The conclusion of the study is pretty clear: Our time here on Earth is finite, and we better find our way off it sooner rather than later.