‘No evidence of primitive life’ in Martian meteorite that lands on Earth

Scientists say a four-billion-year-old meteorite from Mars that hit Earth here decades ago has no evidence of ancient, primitive Martian life.

n 1996, a NASA-led team announced that the organic compounds in the rock appear to have been released by living beings.

Other scientists were skeptical and researchers have done away with that premise for decades, most recently by a team led by Andrew Steele of the Carnegie Institution for Science.

Mr Steele said small samples of the meteorite suggest that the carbon-rich compound is actually water, most likely the result of salty, or briny, water flowing over the rock over a long period of time.

The findings appear in the journal Science.

During Mars’ wet and early past, at least two impacts occurred near the rock, before warming the planet’s surrounding surface, a third impact buoyed it from the Red Planet and into space millions of years ago.

The 4lb (2kg) rock was found in Antarctica in 1984.

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Mars (Mohammed bin Rashid Space Center/AP)

According to the researchers, groundwater moving through cracks in the rock, while it was still on Mars, formed tiny globs of carbon.

The same could happen on Earth, he said, and could help explain the presence of methane in the Martian atmosphere.

But the two scientists who participated in the original study called the findings “disappointing” with these latest findings.

In a shared email, he said he stood by his 1996 comments.

Astronomers Kathy Thomas-Capreta and Simon Klemet of NASA’s Johnson Space Center in Houston wrote, “Although the data presented increase our knowledge of (meteorite), the interpretation is hardly novel, nor is it supported by research.” “

“The unsupported speculation does nothing to solve the puzzle surrounding the origin of organic matter” in meteorites, he said.

According to Mr. Steele, advances in technology made his team’s new findings possible.

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A meteorite labeled ALH84001 is in the hands of a scientist (David J. Phillips/AP).

He praised the measurement by the original researchers and said that their life-claim hypothesis “was a reasonable explanation” at the time.

He said that he and his team, which includes NASA, German, and British scientists, took care to present their results “for what they are, which is a very exciting discovery about Mars and the basic premise.” There is not a study to disprove”.

The discovery is “huge to our understanding of how life began on this planet and helps to refine the techniques we need to find life elsewhere on Mars, or on Enceladus and Europa”, Mr. Steele said in an email, referring to the moons of Saturn and Jupiter along the subsurface of the ocean.

According to Mr Steele, the only way to prove whether there was ever microbial life on Mars is to bring samples to Earth for analysis.

NASA’s Perseverance Mars rover has already collected six samples to return to Earth in a decade or so; three dozen samples desired

Millions of years after drifting into space, the meteorite landed on an ice field in Antarctica thousands of years ago.

The small gray-green piece got its name from Allen Hills 84001, the hills where it was found.