Asteroids might look dry and barren, but the Solar System's biggest asteroid - Ceres - is chock full of water, NASA's Dawn spacecraft has found.
Two different studies published in the journals Nature Astronomy and Science show two distinct pieces of evidence that water ice is abundant at or near the surface of the rocky body.
Today, the water is either frozen as ice, filling pore spaces deep inside Ceres, or locked inside hydrated minerals at the surface. But billions of years ago, early in Ceres's history, heat left over from the Solar System's formation probably kept the asteroid warm inside. This allowed the water to churn and flow, helping to separate Ceres into layers of rock and ice.
