For decades, scientists believed Vesta, one of the largest objects in our solar system’s asteroid belt, wasn’t just an asteroid and eventually concluded it was more like a planet with a crust, mantle and core. Now, new research flips this notion on its head. Astronomers reveals Vesta doesn’t have a core. These findings startled researchers who, until that point, assumed Vesta was a protoplanet that never grew to a full planet.