LONDON – An asteroid containing large diamonds that hit the Earth in 2008came from a “lost” planet in our solar system that existed billions ofyears ago, says a new study.
The parent body from which the celestial rock came was a planetary embryoof a size between Mercury to Mars, said the study published in the journalNature Communications.
The asteroid, now known as “2008 TC3”, was just over four metres indiameter and fell in the Nubian desert in Sudan.
Farhang Nabiei, a materials scientist at the Swiss Federal Institute ofTechnology in Lausanne (EPFL), Switzerland, and his colleagues examined thediamonds from the asteroid which fell into a category of space rocks calledureilites.
“This study provides convincing evidence that the ureilite parent body wasone such large ‘lost’ planet before it was destroyed by collisions some 4.5billion years ago,” the researchers were quoted as saying by EPFL in a newsrelease on Tuesday.
The researchers studied the diamond samples using a combination of advancedtransmission electron microscopy techniques.
The analysis of the data showed that the diamonds had chromite, phosphateand iron-nickel sulfides embedded in them – what scientists refer to as”inclusions”.
These have been known for a long time to exist inside Earth’s diamonds, butare now described for the first time in an extraterrestrial body.
The particular composition and morphology of these materials can only beexplained if the pressure under which the diamonds were formed was higherthan 20 GPa (giga-Pascals, the unit of pressure), according to theresearchers.
This level of internal pressure can only be explained if the planetaryparent body was a Mercury-to Mars-sized planetary “embryo”, depending onthe layer in which the diamonds were formed, the study said.
Many planetary formation models have predicted that these planetary embryosexisted in the first million years of our solar system, and the studyoffers evidence of their existence.