Two rocks found together in Antarctica are chunks of a dwarf planet that was smashed apart early in the solar system’s history, detailed studies suggest. Other remnants of the proto-world may still be floating around in the asteroid belt, and might be identifiable by the spectrum of the sunlight they reflect.

In the solar system’s first few tens of millions of years, collisions between rocky objects and the decay of radioactive isotopes melted the interiors of large objects. Magma oceans – perhaps hundreds of kilometres deep – lapped over the Moon, the Earth, and other large bodies, allowing dense material to settle towards their centres in a process called differentiation.

The two meteorite pieces, called GRA 06128 and GRA 06129 after the Graves Nunataks area of Antarctica where they were found together in 2006, show evidence of such differentiation – which suggests they came from a massive body.

via Meteorites may be remnants of destroyed dwarf planet – space – 13 March 2008 – New Scientist.