Just how those salts ended up on Ceres’ surface is still a mystery, though. Instead of containing large amounts of ice, as some scientists had expected, Ceres’ interior is considerably drier than suspected, reports a second study published Wednesday in Nature Geosciencein Nature Geoscience. That makes it hard to explain how the dwarf planet’s surface ended up covered in formerly dissolved salts. Now, researchers are trying to sort out how Ceres made those salts and moved liquid brines to the surface; they suspect impacts may be to blame for simultaneously melting buried ice and excavating the planet’s salty sea, leaving bits of it to shimmer in the sunlight.

THE WOODLANDS, Texas –

Today, Ceres is a salt-covered dwarf planet whose main