David Bowie finally has an answer to his question – yes, there may be life on Mars.
NASA scientists have discovered water on the red planet’s surface, which flows seasonally as salty liquid, the agency announced Monday during a news conference.
“Today we’re revolutionizing our understanding of this planet,” said Jim Green, NASA director of planetary science. “This is tremendously exciting.”
Scientists previously discovered water in ice form at Mars’ poles, and there is water bound to minerals underneath the planet’s surface; but this is the first time water has been found in liquid form.
John Grunsfeld, associate administrator for the Science Mission Directorate at NASA, said the discovery may prove to be a sign of life.
“The existence of liquid water gives the possibility that, if there is life on Mars, we have a way to describe how it might survive,” he said. “We’re now at a point technologically, we have the capability to go there and ask the question and answer it.”
NASA’s study, published in Nature Geoscience, explains something called the recurring slope lineae, or RSL, which are dark, streaky streams that typically appear on the planet’s surface during the warmer seasons. Spotted by the agency’s Mars Reconnaissance Orbiter spacecraft, the streaks go away during cooler seasons.
Michael Meyer, lead scientist for the Mars Exploration Program, said scientists haven’t been able to figure out, until now, the “waxing and waning of these dark streaks on the surface.”
Lujendra Ojha of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology said his team of researchers found evidence of hydrated salts, including magnesium perchlorate, magnesium chlorate and sodium perchlorate.
“For the first time, we have evidence of the agent that has allowed water to flow on the surface of today’s Mars,” Meyer said.
Scientists are still unsure, however, of where the salty water is coming from — melting ice, an underground layer of permeable rock, or another source.
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