Planetary scientists have long suspected that dark, narrow streaks on the slopes of Mars observed in photos taken by a Ball-built space camera are somehow related to liquid water.
Now analysis of images collected since NASA’s Mars Reconnaissance Orbiter began circling the Red Planet in 2006 suggest a salty brine could be flowing below the surface, greatly advancing the search for life on the Red Planet, scientists reported Monday.
“It’s really cool to be a part of this now, knowing something we worked on a long time ago — 10-12 years ago — is part of it,” said Tom Ebben, who led the Boulder-based Ball Aerospace team that developed the system that allows the spacecraft’s High Resolution Imaging Science Experiment, or HiRISE, to detect light and capture images.
HiRISE is the largest telescopic instrument ever sent beyond Earth’s orbit. Its images are so high resolution that objects as small as one meter across — about the size of a standard coffee table — can be identified.
Although scientists in 2008 confirmed the existence of frozen water on Mars, studying images from HiRISE gave them evidence that strongly suggests water flows during the
summer months. NASA called the results “a major science finding,” but don’t go looking for little green men — yet. Researchers say further exploration is warranted to determine whether any microscopic life exists on the planet.
“It suggests it would be possible for life to be there today,” NASA associate science administrator John Grunsfeld said. “Our quest on Mars has been to follow the water in our search for life in the universe, and now we have convincing science that validates what we’ve long suspected.”
HiRISE images taken over a period of time show a pattern: dark streaks on the Martian mountains — known as recurring slope lineae, or RSL, — ebb and flow over time, appearing during periods when temperatures climbed above minus-10 degrees Fahrenheit.
Yes, that’s summer on Mars.
The patterns were first noted by Lujendra Ojha, who first observed the puzzling RSL in 2010 while an undergraduate at the University of Arizona.
Using another instrument aboard MRO called the Compact Reconnaissance Imaging Spectrometer for Mars, or CRISM, Ojha’s team analyzed minerals content in the RSL areas. They found hydrated salts, which can lower the freezing point of water and melt ice — think about how we salt roads here on Earth — thus potentially creating a liquid brine that scientists believe is shallow subsurface flowing water on present-day Mars.
Ojha, now a PhD student at the Georgia Institute of Technology, is the lead author of the findings published in the journal, Nature Geoscience.
The source of the water is still a mystery. Scientists noted it could be melting ice, an underground aquifer, water vapor from the thin Martian atmosphere, or some combination.
The discovery of the brine — which contains salts called perchlorates — could also open up myriad possibilities for when we send humans to explore the planet, Grunsfeld said, pointing out that Space Shuttle was fueled by ammonium perchlorates: “In principle you could make solid rocket fuel.”
This isn’t the first discovery pointing to salty water on Mars, nor is it the only connection between Mars and the Centennial State.
In August, researchers at the University of Colorado announced evidence of an 18-square-mile chloride salt deposit — roughly the size of the city of Boulder — near the Mars Opportunity rover’s landing site.
Large-scale salt deposits are considered to be evidence of evaporated bodies of water, as seen in locations like Utah’s Bonneville Salt Flats, making the ancient lake the last potentially habitable surface water on the planet, scientists say.
Lockheed Martin Space Systems in Littleton still is involved with MRO flight operations and also with NASA’s Mars Atmosphere and Volatile Evolution, or MAVEN, which is orbiting Mars looking for clues about what happened to the planet’s atmosphere. MAVEN’s chief investigator is CU’s Bruce Jakosky, and the craft was sent to space on a rocket built by Centennial-based United Launch Alliance.
MRO’s planned mission to study the planet’s aqueous history was designed for two Martian years — about 3.8 years here on Earth — but was extended, as many planetary missions often are.
MRO completed its 40,000th orbit around Mars on Feb. 7, and HiRISE hasn’t yet quit.
“It was designed and built to be robust, rugged and meet the basic mission life,” Ebben said.
Ball’s HiRISE team fluctuated between 30-50 people in the early 2000s, and a handful of staff still provides day-to-day operations and support to the University of Arizona-based team that runs the instrument.
HiRISE images also were key to finding hazard-free landing areas for Mars rovers Phoenix, Curiosity and the forthcoming InSight lander, currently in testing at Lockheed Martin’s Waterton Canyon campus for a planned early-2016 launch.
There is plenty more to come.
“Each time we learn something more about Mars it becomes more interesting,” Grunsfeld said at the conclusion of the press conference. “Please stay tuned to science, because basically science never sleeps.”
Laura Keeney: 303-954-1337, lkeeney@denverpost.com or @LauraKeeney
