Study nixes Mars life in meteorite present in Antarctica


CAPE CANAVERAL, Fla. — A 4 billion-year-old meteorite from Mars that prompted a splash right here on Earth a long time in the past incorporates no proof of historic, primitive Martian life in any case, scientists reported Thursday.

In 1996, a NASA-led group introduced that natural compounds within the rock appeared to have been left by residing creatures. Other scientists had been skeptical and researchers chipped away at that premise over the a long time, most lately by a group led by the Carnegie Institution for Science’s Andrew Steele.

Tiny samples from the meteorite present the carbon-rich compounds are literally the results of water — most certainly salty, or briny, water — flowing over the rock for a chronic interval, Steele mentioned. The findings seem within the journal Science.

During Mars’ moist and early previous, no less than two impacts occurred close to the rock, heating the planet’s surrounding floor, earlier than a 3rd influence bounced it off the crimson planet and into area hundreds of thousands of years in the past. The 4-pound rock was present in Antarctica in 1984.

The meteorite labeled ALH84001 is held in the hand of a scientist at a Johnson Space Center lab in Houston, Aug. 7, 1996.The meteorite labeled ALH84001 is held within the hand of a scientist at a Johnson Space Center lab in Houston, Aug. 7, 1996.AP

Groundwater transferring by the cracks within the rock, whereas it was nonetheless on Mars, shaped the tiny globs of carbon which might be current, based on the researchers. The identical factor can occur on Earth and will assist clarify the presence of methane in Mars’ ambiance, they mentioned.

But two scientists who took half within the authentic research took difficulty with these newest findings, calling them “disappointing.” In a shared e mail, they mentioned they stand by their 1996 observations.

“While the data presented incrementally adds to our knowledge of (the meteorite), the interpretation is hardly novel, nor is it supported by the research,” wrote Kathie Thomas-Keprta and Simon Clemett, astromaterial researchers at NASA’s Johnson Space Center in Houston.

“Unsupported speculation does nothing to resolve the conundrum surrounding the origin of organic matter” within the meteorite, they added.

Mars rock Allan Hills 84001, discovered in 1984, is shown at a NASA news conference, Aug. 7, 1996, in Washington. Mars rock Allan Hills 84001, found in 1984, is proven at a NASA information convention, Aug. 7, 1996, in Washington. AP

According to Steele, advances in know-how made his group’s new findings potential.

He recommended the measurements by the unique researchers and famous that their life-claiming speculation “was a reasonable interpretation” on the time. He mentioned he and his group — which incorporates NASA, German and British scientists — took care to current their outcomes “for what they are, which is a very exciting discovery about Mars and not a study to disprove” the unique premise.

This discovering “is huge for our understanding of how life started on this planet and helps refine the techniques we need to find life elsewhere on Mars, or Enceladus and Europa,” Steele mentioned in an e mail, referring to Saturn and Jupiter’s moons with subsurface oceans.

The solely solution to show whether or not Mars ever had or nonetheless has microbial life, based on Steele, is to carry samples to Earth for evaluation. NASA’s Perseverance Mars rover already has collected six samples for return to Earth in a decade or so; three dozen samples are desired.

The meteorite labeled ALH84001 sits in a chamber at a Johnson Space Center lab in Houston, Aug. 7, 1996. Tiny samples from the meteorite present the carbon-rich compounds are literally the results of water.AP

Millions of years after drifting by area, the meteorite landed on an icefield in Antarctica 1000’s of years in the past. The small gray-green fragment acquired its identify — Allan Hills 84001 — from the hills the place it was discovered.

Just this week, a bit of this meteorite was utilized in a first-of-its-kind experiment aboard the International Space Station. A mini scanning electron microscope examined the pattern; Thomas-Keprta operated it remotely from Houston. Researchers hope to make use of the microscope to investigate geologic samples in area — on the moon sooner or later, for instance — and particles that might smash station gear or endanger astronauts.

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