Mineral deposits in Mars' Eridania basin suggest the Red Planet once hosted underwater hydrothermal activity. Photo by NASA/JPL-Caltech/MSSS
Oct. 9 (UPI) -- The discovery of ancient hydrothermal deposits on Mars could offer insights into the origin of life on Earth, according to a team of NASA scientists.
Scientists have previously suggested hydrothermal vents on the ocean floors of early Earth would have offered ideal conditions for the emergence of life. Now, scientists have found evidence of such conditions on Mars.
Researchers discovered the signs of underwater hydrothermal activity while analyzing observations of a basin on southern Mars made by NASA's Mars Reconnaissance Orbiter.
"Even if we never find evidence that there's been life on Mars, this site can tell us about the type of environment where life may have begun on Earth," Paul Niles, a scientist at NASA's Johnson Space Center in Houston, said in a news release. "Volcanic activity combined with standing water provided conditions that were likely similar to conditions that existed on Earth at about the same time -- when early life was evolving here."
Mars is now dry and dormant, but it once hosted water and volcanic activity. Scientists estimate the basin deposits surveyed by MRO were formed roughly 3.7 billion years ago.
Another study published this week argued methane outflows warmed Mars' atmosphere during the time period, melting the planet's ice and allowing water to flow across the Martian surface.
Mars' seas burned off millions of years ago, but hydrothermal activity is still common on the floor of Earth's oceans. Scientists have found complex communities of microbes and other types of organisms uniquely adapted to the niche environment.
Scientists have previously observed signs of hydrothermal activity inside Europa, one of Jupiter's icy moons, as well Enceladus, one of Saturn's 62 moons. Some planetary scientists believe the activity makes them ideal targets in the quest to find extraterrestrial life.
"This site gives us a compelling story for a deep, long-lived sea and a deep-sea hydrothermal environment," Niles said. "It is evocative of the deep-sea hydrothermal environments on Earth, similar to environments where life might be found on other worlds -- life that doesn't need a nice atmosphere or temperate surface, but just rocks, heat and water."
The MRO data suggests the Martian impression was once filled with water, making it the largest sea to grace the Red Planet's surface. Younger lava deposits in the basin prove the region was volcanically active. MRO's spectrometer identified deposits of serpentine, talc and carbonate, minerals created by underwater hydrothermal activity.
Researchers detailed their discovery this week in the journal Nature Communications.
"Ancient, deep-water hydrothermal deposits in Eridania basin represent a new category of astrobiological target on Mars," scientists wrote. "Eridania seafloor deposits are not only of interest for Mars exploration, they represent a window into early Earth."