Are we alone in the universe? Is Earth the only planet that's a suitable home for life? These questions have long motivated scientists as central issues in astrobiology, the search for life in the universe. Astrobiologists compare life on Earth to signs of life on other planets. They test meteorites for evidence of alien bacteria. They collect soil and atmospheric samples from other planets. They study photographs taken on space missions. And they listen for signals from alien civilizations on enormous radio dishes. Learn all about astrobiologists? amazing research in this fast-paced peek into the future of science.