New research from a team including Carnegie's Doug Rumble and Liping Qin focuses on one particularly old type of meteorite called diogenites.
Diogenites are a kind of meteorite that may have come from the asteroid Vesta, or a similar body.
The team examined seven diogenites from Antarctica and two that landed in the African desert.
This new understanding of diogenites gives us a better picture of the earliest days of our Solar System and will help us understand the Earth's birth and infancy," Rumble said.
Scientists have several theories about why this is the case and the research team-which included lead author James Day of Scripps Institution of Oceanography and Richard Walker of the University of Maryland-set out to explore these theories by looking at diogenite meteorites.
A devotee of diogenites for several years, Mittlefehldt analyzed the mineral content of the Allen Hills fragment, known as ALH84001.
In contrast, the same oxide in diogenites contains iron in the doubly ionized form.
He simply wanted to take a close look at a meteorite that researchers had classified as a diogenite.
The three meteorite types -- the eucrites, howardites and diogenites
-- came from an asteroid big enough for its surface rock to melt, possibly from the heat of radioactive elements inside it, concludes a team headed by Dale P.
The closest matches occur between a group of fine-grained igneous meteorites (called howardites, eucrites, and diogenites
, or collectively HEDs) and Vesta.
are dominated by large crystals of a simple, magnesium-rich silicate that cooled slowly from magma.