The strange case of the asteroid planet Vesta

Vesta is the asteroid belt's second largest object, but figuring out what it is has driven astronomers crazy. Is it an asteroid? A planet, perhaps a protoplanet? Whatever the answer, Vesta might just be the solar system's most important object. » 4/26/11 1:00pm 4/26/11 1:00pm

Meet 2 Pallas, The Newest Protoplanet In The Asteroid Belt

With a violent history, a watery origin, and a diameter of 256 kilometers, 2 Pallas is one seriously badass asteroid. In fact, new images of it from the Hubble Telescope have led researchers to dub it a protoplanet. » 10/09/09 7:30am 10/09/09 7:30am