The primary mission of the two Martian rovers is accomplished, NASA announced today in a joint press conference with Jet Propulsion Laboratory and Cornell scientists. “The rocks here were once soaked in liquid water,” said Prof. Steve Squyres ’78 Ph.D. ’81, astronomy, the mission’s principal investigator.
The Spirit and Opportunity landers, which landed on Jan. 3 and Jan. 24, respectively, were sent to assess the likelihood that Mars was once more hospitable to life, focusing on whether or not the planet once held liquid water.
After weeks of drilling and examining their respective areas, and a few days of ambiguous hints from NASA, the rover Opportunity provided strong evidence that the planet was indeed once flowing with water.
“Liquid water once flowed through these rocks. It changed their texture, and it changed their chemistry,” Squyres said during the hour-long press conference.
Squyres gave four main pieces of evidence to support the announcement. The first was the oddly-shaped BB-sized “blueberries” that appeared when Opportunity dug into a rock outcropping by its landing site, Meridiani Planum. These spherically-shaped formations are scattered throughout the layers of rock. This formation indicates that the “blueberries” were deposited over a long time, probably as sedimentary remains when a saturated water solution built up in the rocks.
The second piece of evidence was a series of holes found in the rock. Similar holes, or “vugs,” form on Earth. Salt crystals form inside rocks which sit in salt water, and these crystals are later washed away or dissolved, leaving the vugs behind.
Opportunity’s X-ray spectrometer also indicated high amounts of sulfur, probably in the form of sulfate salts. These salts are generally found in water-soaked environments. Jarosite, which usually indicates the presence of an acidic lake or hot springs, was detected.
Additionally, rock “stripes,” consistent with either wind or water movement, have been noted throughout the crater, and closer inspection is pointing to water as the cause of the stripes.
“This area would have been a good, habitable environment,” said Edward Weiler, associate NASA administrator for space science. NASA was quick to point out that, although Mars had enough water for life, evidence has not yet been found to prove its existence.
NASA was also unable to give a time frame for when the water existed, though Squyres responded negatively when one reporter asked if he thought it was possible that water existed as recently as a few centuries ago.
The rovers, running on solar power, are expected to work for 90 days, although Squyres added that the rovers have been tested for durations four times that long while on Earth. The rovers are expected to explore the nearby areas further. Scientists hope to also explore a nearby crater similar to the one Opportunity is currently in.
Aside from Squyres, many other Cornellians have played prominent roles in the mission. Prof. Jim Bell, astronomy, has been in charge of the PanCam, which has sent back pictures with three to four times higher resolution than any previous mission. Prof. James B. Maas Ph.D. ’66, psychology, has also been doing research on the Mars scientists as they adjust their work schedules to match the longer Martian day, while also advising them on how to cope with the physiological stress it creates. Even science guy Bill Nye ’77 contributed his part by adding the first interplanetary sundial to the rovers.
Archived article by Michael Morisy