Posts Tagged ‘mars’
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Recent findings from NASA’s Curiosity rover led to the announcement that Mars was once habitable. But some scientists believe present-day Mars is still habitable.
The NASA Astrobiology institute and the UK Centre for Astrobiology co-hosted a conference titled “The Present-Day Habitability of Mars” that took place February 4-5 at the University of California Los Angeles. At the conference, Alfred McEwen of the University of Arizona and principal investigator for the HiRise camera aboard NASA’s Mars Reconnaissance Orbiter, stated, “We certainly can’t rule out the possibility that it’s habitable today.”
Space.com reports that McEwen discussed observations by HiRise that suggest briny water may flow down steep slopes on Mars during the planet’s spring and summer. This water is of interest to astrobiologists because it may be a habitable environment for microbes.
Space.com points out that, in places like Antarctica and Chile’s Atacama Desert, “microbes can eke out a living in extremely cold and dry environments.” Scientists continue to study extremophiles–organisms that survive in extreme environments–and Mars-like places here on Earth to better understand the types of environments in which life as we know it can survive.
In the search for life as we know it, potential energy sources are of interest to astrobiologists because, well, life as we know it requires an energy source. Several presenters at the conference discussed a potential energy source found on Mars–perchlorate, a chlorine-containing chemical detected on Mars by NASA’s Phoenix lander in 2008. Carol Stoker of NASA’s Ames Research Center explained that “perchlorate, it turns out, is a potent chemoautotrophic energy source.” According to Space.com, Stoker noted that “the chemical could potentially sustain microbes in the dark Martian subsurface, where photosynthesis is not an option.”
An example of microbes thriving without sunlight was recently discovered here on Earth in the deepest area of the ocean. Reuters recently reported that a Danish-led team of scientists discovered that “Microbes are thriving in surprising numbers at the deepest spot in the oceans, the 11,000-metre (36,000 ft) Mariana Trench in the Pacific, despite crushing pressures in sunless waters.”
Space.com points out that, at the conference, scientists stressed that “Martian life may be able to survive even in places where water doesn’t seep and flow.” What is known about extremophiles on Earth presents many possibilities for life on Mars. And with so much of Mars left unexplored, including the subterranean world of Mars, the possibility of more complex life on the planet cannot be ruled out.
Video from “The Present-Day Habitability of Mars” conference is available HERE.
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Analysis of materials retrieved by NASA’s Curiosity rover has led them to conclude that Mars “could have supported a habitable environment.” NASA tweeted, “Now that we know Mars was habitable, as we continue to explore we’ll learn more about where biosignatures could be preserved.”
The announcement comes after scientists found sulfur, nitrogen, oxygen, phosphorous and carbon in powder drilled out of rocks near an ancient river bed on Mars. These elements are believed to be key ingredients for life. According to NASA, this finding completes one of the rover’s primary missions.
“A fundamental question for this mission is whether Mars could have supported a habitable environment,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program at the agency’s headquarters in Washington. “From what we know now, the answer is yes.”
Paul Mahaffy, principal investigator of the SAM suite of instruments at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, says, “The range of chemical ingredients we have identified in the sample is impressive, and it suggests pairings such as sulfates and sulfides that indicate a possible chemical energy source for micro-organisms.”
NASA clarified in a tweet, “The discovery by @MarsCuriosity of a chloromethane reported today is not proof of past life on Mars.” However, it does answer the question for NASA, officially, as to whether the environment on Mars has ever been conducive to the existence of life. NASA tweeted, “Gale Crater is the first recognized habitable environment found in the solar system beyond Earth.”
Now that one site has been found to have “conditions once suited for ancient life on Mars,” Curiosity will explore other sites that also show promise for having had environments that could have sustained microbial life.
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Curiosity Rover on Mars Predicted to Encounter Moving Sand Dunes
A recent paper by Simone Silvestro of the SETI Institute and colleagues demonstrates that sand dunes in Gale crater, located between the Curiosity rover and its final destination, Aeolis Mons (“Mount Sharp”), are among the actively migrating dunes on Mars.