I’m Maria Zuber, a NASA scientist and a professor at the Massachusetts Institute of Technology. As we explore the universe, we naturally ask, “Is there life on other planets?” So far the answer is, “We don’t know, but we’ll keep searching.” All life on Earth needs liquid water to survive. Since spacecraft haven’t found any liquid water on Mars, scientists think that there is no life on the planet’s surface. But what about below the surface? Spacecraft have discovered frozen water in Mars’ polar ice caps and in clouds of ice crystals. This means that there might be liquid water below the surface where it’s warmer. NASA plans to explore Mars every 26 months. In future missions, we’ll explore below the surface and search for liquid water—and life!