Tanya Kizovski led the Mars meteorite garnet discovery after researchers studying NWA 8171 found the mineral in a fragment from the Royal Ontario Museum in Toronto. The team said it is the first time garnet has been identified in a Martian sample, and it points to a rock type never before detected on Mars.
“This little section of the meteorite looked really interesting and the chemistry was a bit odd,” Kizovski said. Her team initially thought the mineral was pyroxene, then took a second look and found garnet instead.
Royal Ontario Museum in Toronto
The analysis drew on the University of Portsmouth Electron Microscopy and Microanalysis Unit and the Royal Ontario Museum’s specialised laser equipment. James Darling, a professor of Earth and Planetary Science at the University of Portsmouth, was part of the international team with researchers from Universita di Trieste in Italy and the Open University in the UK.
Darling said, “The findings add a striking new dimension to our understanding of the geology of Mars and open an exciting new window into the evolution of our planetary neighbour.”
Ancient Mars and Mars
Kizovski said, “This discovery is going to expand our knowledge of the geologic processes that are possible on this planet. This new garnet-bearing rock type could give us clues to how Mars has changed throughout its history and new insights into the ancient environments that could have formed the garnet and related minerals.” She also said, “Garnet is a classic example of a mineral often found in metamorphic rocks on Earth.”
On Earth, garnet is a cornerstone mineral in geology. For Mars, the finding adds a new mineral record from a planet that is about 4.5 billion years old and has gone through major changes over that span.
Tanya Kizovski and James Darling
Kizovski said, “On Mars, the heat and pressure needed to produce garnet through metamorphism could have come from the impact of a meteorite hitting the surface of Mars, magma rising up into the Martian crust or both.” That leaves the exact formation history of the new garnet-bearing rock type as the next scientific task, and the fragment in NWA 8171 now gives researchers a new sample to work from.
