The meteorite was classified as a nakhlite
, a subgroup of Martian meteorites.
The meteorite that Velbel and his colleagues examined - known as a nakhlite
meteorite - was recovered in 2003 in the Miller Range of Antarctica.
All but one other have been part of the Shergottite, Nakhlite
and Chassignite group, named for the locations where the first of each subtype was discovered.
Dr Susanne Schwenzer, from The Open University, said: "Before we had the detailed study of the nakhlite
meteorites, we did not know that carbonates are forming first, followed by the clays.
* Laboratory-based studies of the SNC (shergottite, nakhlite
, and chassigny) group of meteorites (Nyquist et al.
A microscopic view into a Martian Nakhlite
meteorite shows tunnels (in boxes) that are similar to tunnels associated with DNA in terrestrial rocks.
These "SNC" meteorites (an acronym derived from three of their types: shergottite, nakhlite
, chassignite) are igneous rocks similar in many respects to the rocks that comprise the floors of the Earth's ocean basins.
The meteorite that Velbel and his colleagues examined -- known as a nakhlite
meteorite -- was recovered in 2003 in the Miller Range of Antarctica.
Altogether eight nakhlite
Martian meteorites are known, and all have small but significant differences between them and in their alteration minerals.
Scientists at the University's renowned Space Research Centre, in the Department of Physics and Astronomy, examined five meteorite samples - including the very first nakhlite
, found a century ago.
The findings are based on analysis of radioactive isotopes of rare elements in an ancient meteorite, known as nakhlite
, after the place in Egypt where it was found.
The new specimen is the seventh known member of a group of martian meteorites called the nakhlites
, which scientists propose originated within thick lava flows that solidified on Mars some 1.3 billion years ago.--R.C.