NASA Rover Opportunity Makes Big Discovery, Keeps on Truckin'

NASA's 9-year-old Mars rover Opportunity is on the move again after making a momentous discovery on the Red Planet and defying the limitations of Father Time.

Opportunity — which is nearing its 10th anniversary and has spent the last 20 months working in Cape York (trek below), a raised segment of the Endeavour Crater's western rim — in May inspected a pale rock, called "Esperance" on Matijevic Hill. According to preliminary interpretation, Oppy discovered clay-mineral content formed via intensive alteration by water. The findings, per scientists, suggest that neutral-pH water might have once flowed through the area.

Using a rock abrasion tool, the rover removed Esperance's surface material (above) and then used an alpha particle X-ray spectrometer to identify and assess different levels of aluminum, silica, calcium and iron (shown below).

Matthew Golombek, project scientist for the Mars Exploration Rover Mission, said this water would've been drinkable, and Opportunity's findings were the first positive surface identification of clays.

"That's significant because our previous exploration of Meridiani Planum by Opportunity found sulfate-rich sandstones that formed by the evaporation of extremely acid-rich surface waters in the past," Golombek told Mashable. "Looking at an environment in which the waters were drinkable is considered to be much more conducive to biogenic activity."

Some speculate that Opportunity's Esperance findings (rock pictured above, center) indicate that the Matijevic Hill area would've been covered by a large body of water. Golombek, however, pointed out that there's little in the information that suggests that.

But the fact that water evidence is being unearthed on Mars — a planet now so cold and dry that water couldn't exist on the surface anywhere today — suggests that the ancient past on Mars underwent a radical climatic shift, per Golombek. This is important, he said, because it raises the question: Where did the water go in the drying event?

"The most ancient life that we have evidence for on the Earth is about 3.9, 3.6 billion years ago, and that's roughly the age of the rocks that we're looking at on Mars," he said. "So it poses perhaps one of the most fundamental questions we scientists can ask, 'Are we alone in the universe? Will life form anywhere that liquid water is stable?' That's the clear one requirement we know of that all life uses. 'Or are we a one in a million, one in a trillion chance occurrence that's never to be duplicated elsewhere?'"

Right now, Golombek asserts that life on Mars is inhospitable, noting the low surface pressure and temperatures that make it impossible for liquid water to exist. Golombek said you'd have to go down under the ground, probably kilometers, to find any place where liquid is stable. And in order for the surface to be inhabitable, you'd have to do something in the realm of science fiction (e.g. change the climate, thicken the atmosphere).

In February, NASA's younger Curiosity rover also drilled into Martian rock and discovered clay-mineral composition on the other side of the planet. Spirit (Opportunity's twin from NASA's 2003 Mars Exploration Rover Project), additionally reported findings of wet environments (much of them indicating acidic water, though) on ancient Mars before it ceased operations during its fourth Martian winter, in 2010. Unlike Curiosity, Opportunity does not have a drill or chemistry lab.

Both Spirit and Opportunity fulfilled three-month prime missions and began extra years of extended assignment. Though Opportunity is showing signs of aging, such as loss of motion in some of its joints, scientists are pushing the rover to trek to Solander Point (above), where researchers hope to reveal findings about the different stages in the history of ancient Martian environments.

"Getting to Solander Point will be like walking up to a road cut where you see a cross section of the rock layers," Ray Arvidson of Washington University, St. Louis, deputy principal investigator for the mission, said in a statement.

"There are much stronger orbital indications of clay minerals," Golombek added, with regard to Solander Point. "We're hoping to find other clay minerals and additional geologic associations of those materials to get a better understanding of the environment."

Scientists are crossing their fingers in hopes that Opportunity will get to its next destination by Aug. 1, shortly before the beginning of winter in the planet's southern hemisphere. Opportunity is solar-powered, and it needs to be on a north-facing slope to catch solar insulation, crucial for winter survival on Mars.

Scientists say Opportunity has a new lease on life in its traversing to look at these new materials. According to Golombek, the team hopes to follow up the Esperance findings within the next year or two.

"We are on a pretty strict schedule of driving as fast and far as we can every single day, and we are just a little bit ahead of schedule in terms of getting [to Solander Point] on that time frame," Golombek said. "We're in good shape, and we're going to do everything we can to make sure we are on that north-facing slope. If we're not, then we won't have a rover — and nobody wants that."

Images, video courtesy of NASA/JPL