Ninety days. It was supposed to last for 90 days. It has gone on, doggedly, for 74 months.
When NASA launched the Mars Rovers, Spirit and Opportunity, they hoped the little buggers wouldn't be destroyed on impact. Then, they hoped that the solar arrays could be oriented to provide sufficient power for operations. Then, they waited, breathlessly, for the first transmissions. No one imagined that these marvels would still be exploring Mars, 74 months after launch.
Today they are celebrating a new milestone.
Opportunity Surpasses 20 Kilometers of Total Driving
PASADENA, Calif -- NASA's Mars Exploration Rover Opportunity today surpassed 20 kilometers (12.43 miles) of total driving since it landed on Mars 74 months ago.
The drive taking the rover past that total covered 67 meters (220 feet) southward as part of the rover's long-term trek toward Endeavour Crater to the southeast. It was on the 2,191st Martian day, or sol, of the mission and brought Opportunity's total odometry to 20.0433 kilometers. To reach Endeavour, the healthy but aging rover will need to drive about 12 kilometers (7.5 miles) farther.
Opportunity's mission on Mars was originally planned to last for three months with a driving-distance goal of 600 meters (less than half a mile).
Since landing, Opportunity has examined a series of craters on the plain of Meridiani, and the journey so far has covered a portion of the plain with negligible tilt. Now, the rover is approaching a portion tilting slightly southward. Recent images toward the southwest show the rim of a crater named Bopolu, about 65 kilometers (40 miles) away.
Meanwhile, Spirit, which has had some difficulties, is apparently in hibernation during the Martian winter when available sunlight requires most systems to shut down to conserve power.
Spirit May Have Begun Months-Long Hibernation
MARS EXPLORATION ROVER MISSION STATUS REPORT
PASADENA, Calif. -- NASA's Mars Exploration Rover Spirit skipped a planned communication session on March 30 and, as anticipated from recent power-supply projections, has probably entered a low-power hibernation mode.
In this mode, the rover's clock keeps running, but communications and other activities are suspended in order to put all available energy into heating and battery recharging. When the battery charge is adequate, the rover attempts to wake up and communicate on a schedule it knows.
"We may not hear from Spirit again for weeks or months, but we will be listening at every opportunity, and our expectation is that Spirit will resume communications when the batteries are sufficiently charged," said John Callas of NASA's Jet Propulsion Laboratory, Pasadena, Calif., who is project manager for Spirit and its twin rover, Opportunity.
Spirit's power supply is low because daily sunshine for dusty solar panels is declining with the approach of the winter solstice, in mid-May, in Mars' southern hemisphere. In the three previous Martian winters that Spirit has survived since landing in January 2004, the rover was tilted northward to put its solar panels at a favorable angle toward the sun. That preparation was not possible this winter because of impaired mobility. Spirit's wheels are dug into soft sand, and the rover lost the use of a second wheel four months ago. It had previously lost use of one of its six wheels four years ago.
In this time of threatened violence, abject stupidity, constant disappointment, and a looming feeling of helplessness to effect much of anything, isn't it wonderful to know that humans have exceeded expectations? To know that on the Red Planet, two human creations are performing well beyond expectations, and continue to explore, gather data, and send it back for analysis? To have so brilliantly demonstrated that every once in awhile, we do get something right?