Alien life in our Solar System? Study hints at Saturn’s moon

Enceladus, one of Saturn's many moons. (NASA/AFP)
Updated 27 February 2018
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Alien life in our Solar System? Study hints at Saturn’s moon

PARIS: Humanity may need look no further than our own Solar System in the search for alien life, researchers probing one of Saturn’s moons said Tuesday.
The icy orb known as Enceladus may boast ideal living conditions for single-celled microorganisms known as archaeans found in some of the most extreme environments on Earth, they reported in the science journal Nature Communications.
A methanogenic (methane-producing) archaean called Methanothermococcus okinawensis thrived in laboratory conditions mimicking those thought to exist on Saturn’s satellite, the team said.
On Earth, this type of archaean is found at very hot temperatures near deep-sea hydrothermal vents, and converts carbon dioxide and hydrogen gas into methane.
Traces of methane were previously detected in vapor emanating from cracks in Enceladus’ surface.
“We conclude that some of the CH4 (methane) detected in the plume of Enceladus might, in principle, be produced by methanogens,” the researchers in Germany and Austria wrote.
They also calculated that sufficient hydrogen to support such microbes could be produced by geochemical processes in Enceladus’ rocky core.
The authors had set out to test the hypothesis that conditions on the satellite may be good for hosting methanogenic archaea.
The data, based purely on laboratory study, showed this “could be” so, said Simon Rittmann of the University of Vienna who co-authored the scientific paper.
But the results provide “no evidence for possible extraterrestrial life,” he underlined to AFP.
“Our study only concerns microorganisms. I would like to avoid any speculation about intelligent life,” he said.
Saturn is the sixth planet from the Sun, separated from Earth only by Mars and Jupiter.
It has dozens of moons.
Previous research suggested that Enceladus sports an ocean of liquid water — a key ingredient for life — beneath its icy surface.
The moon is also thought to contain compounds such as methane, carbon dioxide, and ammonia, and its south pole sports hydrothermal activity — a combination of traits that makes it a key target in the search for extra-terrestrial life.
Further research is needed to exclude the possibility that Enceladus’ methane may come from non-biological, geochemical processes, the authors said.


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.