Scientists Use Model to Predict Conditions for Life on Ancient Mars
2022-10-17
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1A new study suggests that ancient Mars might have been able to support a large population of microscopic organisms.
2French scientists used computer models to predict climate and land conditions under the planet's surface about 4 billion years ago.
3The study said the microorganisms might have been growing just beneath the Martian surface.
4The microbes could have been covered by several centimeters of dirt.
5This would have protected them from severe radiation.
6The researchers said any place free of ice on Mars could have been filled with the living organisms.
7But, if they did exist, these simple life forms would have changed the atmosphere so much that they would not have survived the new environment.
8Boris Sauterey was the lead writer of the study, which recently appeared in the publication Nature Astronomy.
9He is a postdoctoral researcher at Sorbonne University in Paris.
10Sauterey said that in the time period studied, Mars was thought to contain lots of water and had less severe conditions than today.
11But he told The Associated Press the research results present a picture of how things can develop in the universe.
12Sauterey said that life on Mars - even simple life like microbes - "might actually commonly cause its own demise."
13He added that while the findings might seem "a bit gloomy," he also finds them exciting.
14The researchers said ancient Mars likely had a wet, warm climate.
15But this environment would have been threatened by large amounts of hydrogen being removed from the thin, carbon dioxide-rich atmosphere.
16Temperatures then dropped by about minus 200 degrees Celsius.
17The researchers said any organisms at or near the surface would likely have buried themselves deeper underground in an attempt to survive.
18This is unlike Earth, where microbes may have helped keep climate conditions more moderate.
19Researchers say this is because Earth had an atmosphere rich in a nitrogen.
20Kaveh Pahlevan is a planetary scientist at the SETI Institute, a nonprofit space research center in California.
21He told the AP he thinks any future models of Mars' climate should consider the new French research.
22Pahlevan recently led a separate study suggesting Mars was born wet with warm oceans that lasted millions of years.
23At the time, the atmosphere would have been dense and mostly hydrogen.
24But over time, some gases were likely transported higher into the atmosphere and lost to space.
25The French study investigated the climate effects of possible microbes when Mars' atmosphere was mostly carbon dioxide.
26So Pahlevan said the research would not relate to earlier times.
27"What their study makes clear, however, is that if (this) life were present on Mars" during this earlier period, "they would have had a major influence on the prevailing climate," Pahlevan said.
28The French researchers offered some suggestions about where to look on Mars for signs of past life.
29They named the Hellas Planitia area, as well as around Jezero Crater.
30Jezero Crater is where the American space agency NASA's exploring vehicle, Perseverance, is carrying out research activities.
31Next, Sauterey said he would like to begin research into the possibility that microbial life could still exist deep within Mars.
32I'm Bryan Lynn.
1A new study suggests that ancient Mars might have been able to support a large population of microscopic organisms. 2French scientists used computer models to predict climate and land conditions under the planet's surface about 4 billion years ago. 3The study said the microorganisms might have been growing just beneath the Martian surface. The microbes could have been covered by several centimeters of dirt. This would have protected them from severe radiation. 4The researchers said any place free of ice on Mars could have been filled with the living organisms. But, if they did exist, these simple life forms would have changed the atmosphere so much that they would not have survived the new environment. 5Boris Sauterey was the lead writer of the study, which recently appeared in the publication Nature Astronomy. He is a postdoctoral researcher at Sorbonne University in Paris. Sauterey said that in the time period studied, Mars was thought to contain lots of water and had less severe conditions than today. 6But he told The Associated Press the research results present a picture of how things can develop in the universe. 7Sauterey said that life on Mars - even simple life like microbes - "might actually commonly cause its own demise." He added that while the findings might seem "a bit gloomy," he also finds them exciting. 8The researchers said ancient Mars likely had a wet, warm climate. But this environment would have been threatened by large amounts of hydrogen being removed from the thin, carbon dioxide-rich atmosphere. Temperatures then dropped by about minus 200 degrees Celsius. The researchers said any organisms at or near the surface would likely have buried themselves deeper underground in an attempt to survive. 9This is unlike Earth, where microbes may have helped keep climate conditions more moderate. Researchers say this is because Earth had an atmosphere rich in a nitrogen. 10Kaveh Pahlevan is a planetary scientist at the SETI Institute, a nonprofit space research center in California. He told the AP he thinks any future models of Mars' climate should consider the new French research. 11Pahlevan recently led a separate study suggesting Mars was born wet with warm oceans that lasted millions of years. At the time, the atmosphere would have been dense and mostly hydrogen. But over time, some gases were likely transported higher into the atmosphere and lost to space. 12The French study investigated the climate effects of possible microbes when Mars' atmosphere was mostly carbon dioxide. So Pahlevan said the research would not relate to earlier times. 13"What their study makes clear, however, is that if (this) life were present on Mars" during this earlier period, "they would have had a major influence on the prevailing climate," Pahlevan said. 14The French researchers offered some suggestions about where to look on Mars for signs of past life. They named the Hellas Planitia area, as well as around Jezero Crater. Jezero Crater is where the American space agency NASA's exploring vehicle, Perseverance, is carrying out research activities. 15Next, Sauterey said he would like to begin research into the possibility that microbial life could still exist deep within Mars. 16I'm Bryan Lynn. 17The Associated Press reported this story. Bryan Lynn adapted the report for VOA Learning English. 18__________________________________________________________________ 19Words in This Story 20post-doctoral -adj. relating to work done after a PhD degree has been completed 21demise - n. the end of something 22gloomy - adj. unhappy and without hope 23prevail - v. to be common among a group of people 24_______________________________________________________________________ 25What do you think of this story? We want to hear from you. We have a new comment system. Here is how it works: 26Each time you return to comment on the Learning English site, you can use your account and see your comments and replies to them. Our comment policy is here.