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.
Image Above: A meteorite found in Antarctica called GRA 06129 may have come from a large body that was blasted apart in a collision early in the solar system (Image: NASA)
