The field of astrobiology includes the search for life elsewhere in our universe. To learn how to look for life on other planets, we must first examine the limits of life as we know it here on Earth. In this Café Sci, C-DEBI Postdoctoral Fellow Dr. Jackie Goordial describes the microorganisms that inhabit some of the most extreme environments on Earth, and discusses how these environments may be similar to other planetary bodies in our solar system and beyond.