Life may have existed on Mars, shows meteorite study


An ancient Martian meteorite has revealed clues that conditions on Mars were once favourable for the development of life, according to researchers.

The meteorite, officially named 'Northwest Africa (NWA) 7034', has a mass of about 320 grams and is made up of glossy-black volcanic material. It was purchased in a Moroccan market in 2011 and then donated to the University of New Mexico (UNM), where Professor Carl Agee, director and curator of the University's Institute of Meteoritics, gathered a team to examine it. The researcher nicknamed the meteorite 'Black Beauty' and after more than a year of study, their published results show it contains nearly 10 times more water than other Martian meteorites. It is one of the oldest Martian meteorites ever found.

"This meteorite is unlike anything I've ever seen before," said Agee in a UNM News statement. "It's a completely new type of Martian meteorite. It has everything in its composition that you'd want in order to further our understanding of the Red Planet. This unique Martian meteorite tells us what vulcanism was like two billion years ago, but it also gives us a glimpse of ancient surface and environmental conditions on Mars that no other meteorite has offered."

"This meteorite, made of brecciated volcanic rock, is consistent with the composition of surface rocks on Mars analyzed by Martian rovers and orbiters," said Agee. "But, our analysis of the oxygen isotopes — oxygen atoms with different numbers of neutrons — shows that NWA 7034 is not like any other meteorites or planetary samples. The chemistry is consistent with surface rocks that interacted with the Martian atmosphere, an idea that has been hypothesized by earlier studies. The abundance of water, some 6,000 parts per million, suggests that the meteorite interacted with Martian surface- or ground-water 2.1 billion years ago."

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Most meteorites found to be from Mars fall into one of three categories — Shergottites, Nakhlites and Chassignites (SNC) — each named after the first meteorite found of its kind.

"The texture of the NWA meteorite is not like any of the SNC meteorites," said Andrew Steele, an astrobiologist at the Carnegie Institution's Geophysical Laboratory, according to Science Recorder. "It is made of cemented fragments of basalt — rock that forms from rapidly cooled lava — dominated with feldspar and pyroxene, most likely from volcanic activity. This composition is common for lunar samples, but not from other Martian meteorites."

"Perhaps most exciting, is that the high water content could mean there was an interaction of the rocks with surface water either from volcanic magma, or from fluids from impacting comets during that time,” Steele added. “It is the richest Martian meteorite, geo­chem­i­cally, and further analyses are bound to unleash more surprises."

Another 'unique' Martian meteorite — Allan Hills 84001 — was discovered in Antarctica in the 1980s, and made headlines in the mid-'90s amid speculation of evidence for ancient Martian microbes. Although this evidence was discounted as having Earthly origins, a 2009 NASA report supported the original finding, showing that, after a painstaking study, researchers concluded that the meteorite did show evidence of microbial fossils and that these microbes were were not of Earth origin. This evidence from 'Black Beauty' of abundant water on the ancient Martian surface certainly adds support to the idea that life once existed on Mars.

"For me personally, this is a once in a career discovery," said Agee. "You try to do high quality science, you do good work, per­se­vere, but once in a while, you just get lucky."

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