Citizen / General public
Researcher
Student / Future student
Company
Public partner
Journalist
Teacher / Pupil

A giant planetary embryo revealed by inclusions in meteorite diamonds

A study by EPFL researchers, in partnership with IPGP, BGI and IUEM, of diamond samples found in a ureilite-type meteorite shows that their formation can only be explained if the original body was a planetary embryo between the size of Mercury and Mars. The article is published in Nature Communications.

A giant planetary embryo revealed by inclusions in meteorite diamonds

Publication date: 02/05/2018

General public, Press, Research

Related themes : Origins

According to current scientific models, the telluric planets in our solar system formed by accretion, following giant energetic impacts of dozens of planetary embryos, between the size of Mercury and Mars. However, traces of these large proto-planets had not yet been found.

Researchers at the Ecole Polytechnique Fédérale de Lausanne (EPFL), in partnership with the Institut de Physique du Globe de Paris (IPGP), the Bavarian Research Institute of Experimental Geochemistry and Geophysics (BGI – University of Bayreuth) and the Institut Universitaire Européen de la Mer (IUEM – University of Western Brittany), have studied diamond samples found in a meteorite that exploded in the Earth’s atmosphere over the Nubian Desert in Sudan in 2008. This Almahata Sitta meteorite (named after the collection of fragments found) is a ureilite, one of the main families of achondritic meteorites whose parent body underwent major impacts during the first ten million years of the solar system. Transmission electron microscopy of these diamonds has revealed inclusions of chromite, phosphate and above all iron and nickel sulphides, whose composition and morphology can only be explained by a formation pressure of over 20 GPa. This level of internal pressure implies that the original body was a planetary embryo of a size between those of Mercury and Mars, providing evidence for the existence of ancient planetary bodies destroyed by accretion.

Diamond inclusions in ureilite by electron microscopy

Ref : Farhang Nabiei, James Badro, Teresa Dennenwaldt, Emad Oveisi, Marco Cantoni, Cécile Hébert, Ahmed El Goresy, Jean-Alix Barrat, Philippe Gillet. A large planetary body inferred from diamond inclusions in a ureilite meteorite. Nature Communications 9, 1327 (17 April 2018). DOI:10.1038/s41467-018-03808-6

Latest news
Release of the IPGP's 2024 Annual Report
Release of the IPGP's 2024 Annual Report
The IPGP annual report, in both French and English, aims to share our enthusiasm for all the research we conduct with as many people as possible. It p...
Director position of the Institut de physique du globe de Paris (IPGP)
Director position of the Institut de physique du globe de Paris (IPGP)
The position of Director of the Institut de Physique du Globe de Paris (IPGP) is vacant as of March 24, 2026.
IPGP is now on Twitch!
IPGP is now on Twitch!
Following on from the MOOC Notre Planète (Our Planet), which is still open for enrolment, the Institut de Physique du Globe de Paris is launching its ...
Three ERC advanced grants awarded to the IPGP: new advances in cosmochemistry and planetary sciences
Three ERC advanced grants awarded to the IPGP: new advances in cosmochemistry and planetary sciences
The Institut de physique du globe de Paris (IPGP) has just been awarded three advanced grants from the European Research Council (ERC) for projects le...