Studies of meteorites found in Antarctica have shown that there is no life on Mars

Study nixes Mars life in meteorite found in Antarctica 张天财编译自ABC News

作者MARCIA DUNN AP Aerospace Writer

14 January 2022, 11:02 PM January 14, 2022

Scientists have concluded that a meteorite from Mars contains no evidence of ancient Martian life Scientists have concluded that a meteorite from Mars contains no signs of ancient life on Mars.

CAPE CANAVERAL, Fla. -- A 4 billion-year-old meteorite from Mars that caused a splash here on Earth decades ago contains no evidence of ancient, primitive Martian life after all, scientists reported Thursday. A 4 billion-year-old meteorite from Mars that caused a stir on Earth decades ago. The meteorite landed thousands of years ago on an ice sheet in Antarctica. On January 14, 2022, scientists reported that the meteorite contained no primitive, ancient signs of life.

In 1996, a NASA-led team announced that organic compounds in the rock appeared to have been left by living creatures. In 1996, a research team led by NASA announced that the organic compounds in the rock appeared to be left behind by the organisms.

Other scientists were skeptical and researchers chipped away at that premise over the decades, most recently by a team led by the Carnegie Institution for Science’s Andrew Steele. At the time, other scientists were skeptical. For decades, scientists have been studying the meteorite.

Tiny samples from the meteorite show the carbon-rich compounds are actually the result of water — most likely salty, or briny, water — flowing over the rock for a prolonged period, Steele said. Tiny samples taken from meteorites suggest that these carbon-rich compounds are actually the result of the long-term flow of water on the rock.

The findings appear in the journal Science. The findings were published in the journal Science.

The 4-pound (2-kilogram) rock was found in Antarctica in 1984. Groundwater moving through the cracks in the rock, while it was still on Mars, formed the tiny globs of carbon that are present, according to the researchers. The 2 kg meteorite was discovered in Antarctica in 1984. Researchers believe that while the rock was still on Mars, groundwater flowed through its cracks, forming tiny carbon droplets that existed.

The same thing can happen on Earth and could help explain the presence of methane in Mars' atmosphere, they said. This happens the same way on Earth, which also helps explain why methane is present in the Martian atmosphere.

The following original text is for reference only.

But two scientists who took part in the original study took issue with these latest findings, calling them “disappointing." In a shared email, they said 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” in the meteorite, they added. According to Steele, advances in technology made his team's new findings possible. He commended the measurements by the original researchers and noted that their life-claiming hypothesis “was a reasonable interpretation" at the time. He said 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 not a study to disprove” the original premise. This finding “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 said in an email, referring to Saturn and Jupiter’s moons with subsurface oceans. The only way to prove whether Mars ever had or still has microbial life, according to Steele, is to bring samples to Earth for analysis. NASA's Perseverance Mars rover already has collected six samples for return to Earth in a decade or so; three dozen samples are desired. Millions of years after drifting through space, the meteorite landed on an icefield in Antarctica thousands of years ago. The small gray-green fragment got its name — Allan Hills 84001 — from the hills where it was found. Just this week, a piece of this meteorite was used in a first-of-its-kind experiment aboard the International Space Station. A mini scanning electron microscope examined the sample; Thomas-Keprta operated it remotely from Houston. Researchers hope to use the microscope to analyze geologic samples in space — on the moon one day, for example — and debris that could ruin station equipment or endanger astronauts.