Dormant desert life hints at possibilities on Mars

Updated 27 February 2018
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Dormant desert life hints at possibilities on Mars

MIAMI: It may rain once a decade or less in South America’s Atacama Desert, but tiny bacteria and microorganisms survive there, hinting at the possibility of similar life on Mars, researchers said Monday.
The desert, which spans parts of Chile and Peru, is the driest non-polar desert on Earth and may contain the environment most like that of the Red Planet, said the report in the Proceedings of the National Academy of Sciences.
Lead researcher Dirk Schulze-Makuch, a professor and planetary scientist at the Technical University of Berlin, and colleagues took a trip to the desert in 2015 to learn more about what kind of life might exist there. Then, unexpectedly, it rained.
Scientists detected an explosion of biological activity in the soil, and quickly began using sterile spoons to scoop up samples.
Genomic analyzes helped identify the several apparently indigenous species of microbial life — mostly bacteria — that had somehow adapted to live in the harsh environment by lying dormant for years, then re-animating and reproducing once it rained.
“In the past, researchers have found dying organisms near the surface and remnants of DNA, but this is really the first time that anyone has been able to identify a persistent form of life living in the soil of the Atacama Desert,” Schulze-Makuch said.
“We believe these microbial communities can lay dormant for hundreds or even thousands of years in conditions very similar to what you would find on a planet like Mars and then come back to life when it rains.”
Scientists returned to the Atacama in 2016 and 2017 for follow-up visits and discovered that the same microbial communities in the soil were gradually reverting to their dormant state.
But they did not completely die off. Single-celled organisms, found mainly in the deeper layers of the desert, “have formed active communities for millions of years and have evolved to cope with the harsh conditions,” said the PNAS report.
Since Mars had oceans and lakes billions of years ago, researchers say early life forms may have thrived there, too.
The world’s space agencies are sending robotic vehicles to Mars in a bid to uncover signs of life, but any attempt to return samples to Earth will be costly and complicated.
Schulze-Makuch said the research may help scientists home in on ways to study Martian microbes, which might have evolved to the planet’s colder, drier climate over time, much like the Atacama microbes.
“We know there is water frozen in the Martian soil and recent research strongly suggests nightly snowfalls and other increased moisture events near the surface,” he said.
“If life ever evolved on Mars, our research suggests it could have found a subsurface niche beneath today’s severely hyper-arid surface.”


Japan space probe Hayabusa2 drops hopping rovers toward asteroid

Updated 21 September 2018
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Japan space probe Hayabusa2 drops hopping rovers toward asteroid

  • If the mission is successful, the rovers will conduct the world’s first moving, robotic observation of an asteroid surface
  • The Hayabusa2 mission was launched in December 2014 and will return to Earth with its samples in 2020

TOKYO: A Japanese space probe Friday released a pair of exploring rovers toward an egg-shaped asteroid to collect mineral samples that may shed light on the origin of the solar system.
The “Hayabusa2” probe jettisoned the round, cookie tin-shaped robots toward the Ryugu asteroid, according to the Japan Aerospace Exploration Agency (JAXA).
If the mission is successful, the rovers will conduct the world’s first moving, robotic observation of an asteroid surface.
Taking advantage of the asteroid’s low gravity, they will jump around on the surface — soaring as high as 15 meters and staying in the air for as long as 15 minutes — to survey the asteroid’s physical features with cameras and sensors.
So far so good, but JAXA must wait for the Hayabusa2 probe to send data from the rovers to Earth in a day or two to assess whether the release has been a success, officials said.
“We are very much hopeful. We don’t have confirmation yet, but we are very, very hopeful,” Yuichi Tsuda, JAXA project manager, told reporters.
“I am looking forward to seeing pictures. I want to see images of space as seen from the surface of the asteroid,” he said.
The cautious announcement came after a similar JAXA probe in 2005 released a rover which failed to reach its target asteroid.
Next month, Hayabusa2 will deploy an “impactor” that will explode above the asteroid, shooting a two-kilo (four-pound) copper object into the surface to blast a crater a few meters in diameter.
From this crater, the probe will collect “fresh” materials unexposed to millennia of wind and radiation, hoping for answers to some fundamental questions about life and the universe, including whether elements from space helped give rise to life on Earth.
The probe will also release a French-German landing vehicle named Mobile Asteroid Surface Scout (MASCOT) for surface observation.
Hayabusa2, about the size of a large fridge and equipped with solar panels, is the successor to JAXA’s first asteroid explorer, Hayabusa — Japanese for falcon.
That probe returned from a smaller, potato-shaped, asteroid in 2010 with dust samples despite various setbacks during its epic seven-year odyssey and was hailed a scientific triumph.
The Hayabusa2 mission was launched in December 2014 and will return to Earth with its samples in 2020.