The longest-lived robot ever sent from Earth to the surface of another planet, Opportunity snapped pictures of a strange landscape and revealed surprising glimpses into the distant past of Mars for over 14 years. But on Wednesday, NASA announced that the rover is dead.
“It is therefore that I am standing here with a deep sense of appreciation and gratitude that I declare the Opportunity mission is complete,” said Thomas Zurbuchen, NASA’s associate administrator for science.
For the scientists, that ends a mission of unexpected endurance. The rover was designed to last only three months. Opportunity provided scientists a close-up view of Mars that they had never seen: finely layered rocks that preserved ripples of flowing water several billion years ago, a prerequisite for life.
The steady stream of photographs and data from Opportunity — as well as its twin, Spirit, which survived until 2010 — also brought Mars closer to people on Earth. Because the rovers continued so much longer than expected, NASA has now had a continuous robotic presence on Mars for more than 15 years.
That streak seems likely to continue for many more years. A larger, more capable rover, Curiosity, arrived in 2012, and NASA is planning to launch another in 2020.
“Rovers and their observations resonate with people,” said Raymond E. Arvidson, a professor of planetary geology at Washington University in St. Louis and the deputy principal investigator for the mission. “It’s as if you were walking on the surface. It has that kind of perspective, and it’s not a particularly alien landscape.”
On Tuesday night, NASA made one last call to Opportunity, which was silenced last summer by a giant dust storm. There was no answer.
“It was an incredibly somber moment,” said Tanya Harrison, a member of the mission’s science team who was present in Pasadena, Calif., at the Jet Propulsion Laboratory during the final attempt to reach the rover. “Just waiting for the inevitable, basically.”
The rover has been quiet since June. During the dust storm, Opportunity’s solar panels could not generate enough power to keep the spacecraft awake.
“There were some who were willing to give up quite quickly, but there was a huge backlash,” Dr. Harrison said. “We didn’t feel like the rover was being given a fair chance.”
NASA relented, but as time passed, it became more likely that the mission was finally over.
Perhaps the solar panels are encrusted in a thick layer of dust, or some crucial electronic component broke down in the extremes of Martian weather.
The windy season, when gusts have periodically cleaned the solar panels, has now ended, further reducing the chances of a revival.