NASA Rover Captures Rock Showing Possible Signs of Microbial Life
2024-08-05
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1A Mars explorer operated by the American space agency NASA has captured a rock that scientists say shows possible signs of ancient microbial life.
2NASA said in a recent statement that the Perseverance explorer, or rover, collected the rock on July 21.
3Scientists working on the Perseverance team nicknamed the rock "Cheyava Falls," after the tallest waterfall in the Grand Canyon.
4The rover's exploration area is believed to include a former river valley measuring about 400 meters wide.
5The valley is thought to have formed by water rushing into Jezero Crater billions of years ago.
6Scientists believe the area around Jezero Crater contained large bodies of water in the distant past.
7NASA's statement says the rock shows signs of "chemical signatures and structures that could possibly have been formed by life billions of years ago..."
8NASA team members based their findings on examinations of the rock with imaging equipment and multiple scientific instruments.
9But they noted that additional research is needed to confirm a history of microbial life.
10The examinations did suggest the rock contains "organic compounds," NASA said.
11But the statement added, "While such carbon-based molecules are considered the building blocks of life, they also can be formed by non-biological processes."
12Perseverance uses its robotic arm and drilling equipment to capture rock and soil samples from the Martian surface.
13So far, it has collected 22 samples.
14The rover has secured the samples in special containers and they are to be picked up and returned to Earth during a future mission.
15Ken Farley is a project scientist with the Perseverance team at Caltech in Pasadena, California.
16He said, "Cheyava Falls is the most puzzling, complex, and potentially important rock yet investigated by Perseverance."
17Farley said unusual color spots and other structural elements in the samples suggest "chemical reactions" that might have given energy to ancient microbial life.
18But he noted that so far, scientists have not been able to identify exactly how the rock formed.
19The team described the rock as containing white veins that may have been created by the substance calcium sulfate.
20Between the veins, examiners found lines of material with a reddish color.
21These lines suggest the presence of hematite, a common substance found in many rocks on Earth.
22David Flannery is an astrobiologist and member of the Perseverance science team from the Queensland University of Technology in Australia.
23He said that on Earth, these kinds of rock elements are often linked "with the fossilized record of microbes living in the subsurface."
24The scientists said the new findings strengthen existing evidence that such rocks may have been created or were changed by flowing water on Mars billions of years ago.
25Caltech's Farley said the rock sample had already been imaged and examined with lasers, X-ray equipment and other instruments as much as possible in recent weeks.
26He noted that Perseverance has done as much as it can to examine the newly discovered samples.
27Farley added, "To fully understand what really happened in that Martian river valley at Jezero Crater billions of years ago, we'd want to bring the Cheyava Falls sample back to Earth."
28That way, he said, "it can be studied with the powerful instruments available in laboratories."
29I'm Bryan Lynn.
1A Mars explorer operated by the American space agency NASA has captured a rock that scientists say shows possible signs of ancient microbial life. 2NASA said in a recent statement that the Perseverance explorer, or rover, collected the rock on July 21. Scientists working on the Perseverance team nicknamed the rock "Cheyava Falls," after the tallest waterfall in the Grand Canyon. 3The rover's exploration area is believed to include a former river valley measuring about 400 meters wide. The valley is thought to have formed by water rushing into Jezero Crater billions of years ago. Scientists believe the area around Jezero Crater contained large bodies of water in the distant past. 4NASA's statement says the rock shows signs of "chemical signatures and structures that could possibly have been formed by life billions of years ago..." 5NASA team members based their findings on examinations of the rock with imaging equipment and multiple scientific instruments. But they noted that additional research is needed to confirm a history of microbial life. 6The examinations did suggest the rock contains "organic compounds," NASA said. But the statement added, "While such carbon-based molecules are considered the building blocks of life, they also can be formed by non-biological processes." 7Perseverance uses its robotic arm and drilling equipment to capture rock and soil samples from the Martian surface. So far, it has collected 22 samples. The rover has secured the samples in special containers and they are to be picked up and returned to Earth during a future mission. 8Ken Farley is a project scientist with the Perseverance team at Caltech in Pasadena, California. He said, "Cheyava Falls is the most puzzling, complex, and potentially important rock yet investigated by Perseverance." 9Farley said unusual color spots and other structural elements in the samples suggest "chemical reactions" that might have given energy to ancient microbial life. But he noted that so far, scientists have not been able to identify exactly how the rock formed. 10The team described the rock as containing white veins that may have been created by the substance calcium sulfate. Between the veins, examiners found lines of material with a reddish color. These lines suggest the presence of hematite, a common substance found in many rocks on Earth. 11David Flannery is an astrobiologist and member of the Perseverance science team from the Queensland University of Technology in Australia. He said that on Earth, these kinds of rock elements are often linked "with the fossilized record of microbes living in the subsurface." 12The scientists said the new findings strengthen existing evidence that such rocks may have been created or were changed by flowing water on Mars billions of years ago. 13Caltech's Farley said the rock sample had already been imaged and examined with lasers, X-ray equipment and other instruments as much as possible in recent weeks. He noted that Perseverance has done as much as it can to examine the newly discovered samples. 14Farley added, "To fully understand what really happened in that Martian river valley at Jezero Crater billions of years ago, we'd want to bring the Cheyava Falls sample back to Earth." That way, he said, "it can be studied with the powerful instruments available in laboratories." 15I'm Bryan Lynn. 16Bryan Lynn wrote this story for VOA Learning English, based on reports from NASA and Agence-France Presse. 17___________________________________________ 18Words in This Story 19nickname - n. a name used informally instead of an official name 20crater - n. a hole left in the ground by an object that hits it with a huge force 21signature - n. a feature in the appearance or qualities of a natural object 22drill - v. to make a hole in a hard substance using a special tool 23puzzling - adj. difficult to understand or figure out 24vein - n. one of the thin lines found on an object 25fossil - n. part of a plant or animal from many years ago that has been preserved in rock