The ROM Helps Solve An Age-Old Martian Mystery
In a major discovery released in late July in the respected scientific journal Nature, a team including Royal Ontario Museum curator of mineralogy Dr. Kim Tait has provided the conclusive answer to a longstanding debate about the age of Martian meteorites. The research has determined that at least some of the surface of Mars is quite a bit younger than most scientists have believed.
The multinational team included scientists from the ROM, the University of Western Ontario, the University of Wyoming, the University of California, Los Angeles, and the University of Portsmouth in the UK.
They focused on NWA 5298, a piece of an extraordinary Martian meteorite found in northwest Africa that is part of the ROM’s world-leading collection.
Kim Tait, Curator
By examining the precise composition of tiny crystals found in the meteorite, Tait and the team determined that it had been part of a lava flow on Mars some 200 million years ago. Their work also revealed crystals that grew later, when the meteorite was launched from Mars towards Earth. This allowed the team to narrow down the timing of the meterorite to less than 20 million years ago while also identifying possible launch source locations on the flanks of supervolcanoes at the Martian equator.
In doing so, the team has shed stunning new light on the planet, its origins and composition. With the team’s research findings, Tait and her colleagues provide a much clearer picture of Mars and its nature: “We have learned something very important about the application of geochronology and about the Red Planet itself,” said Dr. Tait.
An optical image of a slice of Martian meteorite NWA 5298, mounted for growth history analysis of the crystals and isotopic dating using electron and ion beam techniques. The Martian lava flow cooled to form the interlocking mineral texture ~200 million years ago. Note dark patches are glass generated by heating during launch of the meteorite Earthward less than 20 million years ago.
Full details can be found in Nature, in a paper entitled, “Solving the Martian meteorite age conundrum using micro-baddeleyite and launch-generated zircon.”
The ROM’s Earth Sciences section currently is involved in a number of groundbreaking studies focused on Mars, including providing critical samples of Martian meteorites that will assist in analyzing scientific data collected by the Mars rover Curiosity.
In related news, the ROM is now confirming acquisition of the newest addition to the ROM’s mineralogy collection: NWA 7042. Another Martian meteorite found in Northwest Africa, NWA 7042 is the fourth-largest single-mass shergottite in existence and the fifth largest among all known Martian meteors. Shergottites are similar to the basalt we find in abundance here on Earth. It is also one of about only 70 distinct Martian meteorites that have been confirmed.
Weighing 2.98 kilograms, NWA 7042 will be the centrepiece of the ROM’s impressive display of 15 meteorites from the Red Planet. ROM visitors can view the Martian rocks for a limited time in the Teck Suite of Galleries: Earth’s Treasures.
This finding (and the images 1 and 3 were also published in HuffPost (Image 1;3) and Space.com (Image 3)
Source: The Rom (Royal Ontario Museum)