WASHINGTON — NASA’s InSight Mars lander mission is likely to be completed by the end of the year as power levels for the spacecraft continue to decline, project officials confirmed on May 17.
During a briefing about the mission, which has been on the surface of Mars since November 2018, project leaders said science operations are likely to end in July as the output of the spacecraft’s two solar panels, covered in dust, falls below critical levels. drops. Increasing dust levels in the atmosphere due to seasonal changes exacerbate the power loss.
In the coming weeks, controllers will begin shutting down some science instruments while placing the lander’s robotic arm in a “retirement” position, with the camera pointed to view the lander’s primary instrument, a seismometer. That seismometer, which has been running continuously for most of the mission, will switch to intermittent operations this summer to conserve power, before shutting down completely later this summer.
The shutdown of the seismometer, which would end the lander’s science operations, could be as early as mid-July, said Kathya Zamora Garcia, InSight’s deputy project manager. The project expects to maintain occasional contact, including the occasional image from the camera, until the end of this year, when the power level drops below what is needed to run at all.
There is some uncertainty in that schedule, including hopes that the lander could last longer. “We’re in a regime we’ve never been in before,” said Bruce Banerdt, principal investigator for InSight at JPL. “If the power goes out, we don’t really know exactly how well the spacecraft will perform. It has exceeded our expectations at just about every turn on Mars. It may take longer than that.”
The project had warned for some time that as dust continued to build up on the lander’s solar panels, its power would drop and jeopardize the mission. Banerdt said at an advisory committee meeting in February that the power level would fall below what is needed to operate scientific instruments by May or June, and below “survivability” for the lander itself by the end of the year.
Banerdt and others had hoped for a “clean up” to remove dust from the panels, such as a dust devil or gust of wind. The panels generated 5,000 watt-hours of energy per day on Mars when they landed, but now produce only a tenth of that. Even a modest cleaning event could boost the power level enough to keep the mission going.
Engineers tried other means of cleaning the solar panels, using the robotic arm to scoop up regolith and drop it near the arrays, allowing the wind to pick up grains and bounce them off the arrays, causing loose build-up. fabric was shaken. That provided a temporary boost to power, which Garcia said would provide another four to six weeks of operations for the lander’s instruments.
Banerdt said afterwards that he wished the lander had some sort of mechanism to remove dust from the arrays, but that was one of the trade-offs in making the mission fit within the Discovery program’s cost cap. “If we put more money into the solar panels, we would have to put less money into the scientific instruments, so we tried to strike the right balance,” he said.
Despite its imminent demise, NASA called InSight a success, well beyond its primary mission of one Martian year. That assessment comes even though one of its key instruments, a heat flow probe, was unable to burrow into the surface as planned due to soil conditions that the instrument’s designers had not foreseen based on what had been seen at other landing sites on the planet.
That success includes the strongest “Marsquake” yet measured by the lander on May 4, estimated at a magnitude of 5. Banerdt said scientists are still analyzing the data to try to pinpoint the quake’s source, which is outside. seems to be a known error. zone.
“There hasn’t really been much doom and gloom in the team. We’re still focused on piloting the spacecraft,” he added. “We’re still figuring out how to get the most science out of it.”
The project doesn’t rule out trying to reestablish contact with InSight next year, should a cleaning event remove dust from the arrays. NASA’s recent senior review of planetary missions found that there is a slim chance of doing so by mid-2023 after the winter season at the landfall.
“The environment of Mars is very uncertain. We don’t know what’s going to happen,” Garcia said, with communications sessions scheduled just in case. “We’ll listen.”