The space agency has just achieved 5,000 sols for the Mars Opportunity rover, which was only supposed to last for 90.
NASA’s Mars Opportunity rover was only supposed to last 90 “sols,” or Martian days, when it arrived on the surface of the Red Planet on Jan. 25, 2004. More than 14 years later, she’s still going strong, and as we reported recently just achieved its 5,000th sol on Feb. 17. But it’s the incredible story and discoveries of Opportunity that make this truly an incredible accomplishment by NASA.
The reason why the Opportunity mission was only supposed to last 90 sols was because scientists did not think the solar-powered vehicle would be able to endure even one Martian winter, but so far it’s been able to survive eight. The plucky rover’s endurance was so impressive that NASA named the region it was exploring “Perserverance Valley.”
And it has racked up an impressive list of accomplishments since it began its mission those many years ago. It has documented and characterized a huge range of rocks and soils, and discovered evidence of past water activity on Mars. Opportunity has also been able to send back atmospheric and astronomical data back to NASA.
Back in July 2014, the Opportunity rover achieved the longest off-world distance traveled of 40 kilometers, beating out the Lunokhod 2, which traversed 39 kilometers on the moon as part of a 1970s Soviet mission. And in March 2015, the Opportunity officially reached the distance run in a marathon race, traveling 42.195 kilometers, or 26.219 miles.
The following is a statement from NASA on the accomplishment.
The Sun will rise on NASA’s solar-powered Mars rover Opportunity for the 5,000th time on Saturday, sending rays of energy to a golf-cart-size robotic field geologist that continues to provide revelations about the Red Planet.
“Five thousand sols after the start of our 90-sol mission, this amazing rover is still showing us surprises on Mars,” said Opportunity Project Manager John Callas, of NASA’s Jet Propulsion Laboratory, Pasadena, California.
A Martian “sol” lasts about 40 minutes longer than an Earth day, and a Martian year lasts nearly two Earth years. Opportunity’s Sol 1 was landing day, Jan. 25, 2004 (that’s in Universal Time; it was Jan. 24 in California). The prime mission was planned to last 90 sols. NASA did not expect the rover to survive through a Martian winter. Sol 5,000 will begin early Friday, Universal Time, with the 4,999th dawn a few hours later. Opportunity has worked actively right through the lowest-energy months of its eighth Martian winter.
From the rover’s perspective on the inside slope of the western rim of Endeavour Crater, the milestone sunrise will appear over the basin’s eastern rim, about 14 miles (22 kilometers) away. Opportunity has driven over 28 miles (45 kilometers) from its landing site to its current location about one-third of the way down “Perseverance Valley,” a shallow channel incised from the rim’s crest of the crater’s floor. The rover has returned about 225,000 images, all promptly made public online.
“We’ve reached lots of milestones, and this is one more,” Callas said, “but more important than the numbers are the exploration and the scientific discoveries.”
The mission made headlines during its first months with the evidence about groundwater and surface water environments on ancient Mars. Opportunity trekked to increasingly larger craters to look deeper into Mars and father back into Martian history, reaching Endeavour Crater in 2011. Researchers are now using the rover to investigate the processes that shaped Perseverance Valley.
The following is a NASA statement on a recent Opportunity discovery.
NASA’s Mars Exploration Rover Opportunity keeps providing surprises about the Red Planet, most recently with observations of possible “rock stripes.”
The ground texture seen in recent images from the rover resembles a smudged version of very distinctive stone stripes on some mountain slopes on Earth that result from repeated cycles of freezing and thawing of wet soil. But it might also be due to wind, downhill transport, other processes or a combination.
Opportunity landed on Mars in January 2004. As it reaches the 5,000th Martian day, or sol, of what was planned as a 90-sol mission (see related story), it is investigating a channel called “Perseverance Valley,” which descends the inboard slope of the western rim of Endeavour Crater.
“Perseverance Valley is a special place, like having a new mission again after all these years,” said Opportunity Deputy Principal Investigator Ray Arvidson of Washington University in St. Louis. “We already knew it was unlike any place any Mars rover has seen before, even if we don’t yet know how it formed, and now we’re seeing surfaces that look like stone stripes. It’s mysterious. It’s exciting. I think the set of observations we’ll get will enable us to understand it.”
On some slopes within the valley, the soil and gravel particles appear to have become organized into narrow rows or corrugations, parallel to the slope, alternating between rows with more gravel and rows with less.
The origin of the whole valley is uncertain. Rover-team scientists are analyzing various clues that suggest actions of water, wind or ice. They are also considering a range of possible explanations for the stripes, and remain uncertain about whether this texture results from processes of relatively modern Mars or a much older Mars.
Other lines of evidence have convinced Mars experts that, on a scale of hundreds of thousands of years, Mars goes through cycles when the tilt or obliquity of its axis increases so much that some of the water now frozen at the poles vaporizes into the atmosphere and then becomes snow or frost accumulating nearer the equator.