NASA’s InSight spacecraft isn’t quite dead yet.
But InSight, a stationary robotic probe on Mars, is fading as dust builds up on its solar panels. Mission managers predict that by the end of the summer it will not have enough energy to continue operating its instruments and that it will come to a standstill by the end of the year.
“That’s just because of the lack of energy,” Kathya Zamora Garcia, the mission’s deputy project scientist, said at a news conference Tuesday.
The spacecraft could be lucky if a dust devil – a miniature whirlwind that whirls across the Martian landscape – passes by and blows the dust off the solar panels. Although several thousand dust devils have been detected in the area, not a single InSight has done any useful cleaning.
“We’re not too hopeful, considering it’s been three and a half years now and we haven’t seen one,” said Bruce Banerdt, InSight’s principal investigator, “but it could still happen.”
When InSight landed in November 2018, the pristine solar panels on Mars generated 5,000 watt-hours of energy every day. Now, shrouded in dust, they produce a tenth as much.
The spacecraft fulfilled its primary objectives during its two-year primary mission; NASA then approved a two-year extension through the end of 2022.
As the energy dwindles, the managers will begin to turn off the spacecraft’s instruments and put away the mechanical arm. They will try to run the craft’s main scientific tool, a sensitive seismometer, for as long as possible, although in a few weeks they will start using it only part of the day, or maybe even every other day, rather than continuously. .
Ms. Garcia said the seismometer should probably be shut down completely sometime in July. After that, there’s just enough energy to check in with radio communications and maybe take the occasional photo.
Once InSight loses power, it will join a series of NASA missions stranded on the red planet after long, successful flights, including the two Viking landers that crashed in 1976 and the Spirit and Opportunity rovers that arrived in 2004. for 90-day missions, but lasted for years. NASA has two other rovers and an experimental helicopter studying the surface of Mars, and China has one rover in use there.
Most of NASA’s missions to Mars over the past two decades have focused on the possibility that the fourth planet from the sun was once hospitable to life.
InSight — the name is a compression of the mission’s full name, Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport — was a diversionary manoeuvre, focusing instead on the mysteries of Mars’ deep interior. The $830 million mission was designed to answer questions about the planet’s structure, composition and geological history.
Mars lacks plate tectonics, the shifting bits of crust that make up our planet’s surface. But Marsquakes do occur nonetheless, driven by other tectonic stresses, such as the shrinking and cracking of the crust as it cools.
During its mission, InSight recorded more than 1,300 Marsquakes. Just two weeks ago, it recorded the largest Mars quake to date: a magnitude of 5.0, modest by Earth standards, but at the higher end of what scientists had expected for Mars.
The epicenter of the 5.0 magnitude quake was near a series of fissures known as Cerberus Fossae, where many previously detected Marsquakes had occurred, said Dr. banerdt. But, he added: “It’s not really in Cerberus Fossae, which is interesting. And we don’t quite understand that yet.”
He said the scientists had only two weeks to analyze the data, but they could see the seismic signals clearly, and the quake could have been big enough to make Mars vibrate like a bubble, albeit at frequencies too low. are to be observed. heard.
“This earthquake really becomes a wealth of scientific information if we sink our teeth into it,” said Dr. banerdt.
By listening to the echoes of the seismic waves bouncing around Mars, InSight produced data that could be turned into a three-dimensional map of the planet.
The crust turned out to be thinner than expected and appears to consist of three underlayers. The seismic signals also measured the core’s size: about 2,300 miles in diameter.
The seismometer revealed not only what was below, but also the dynamics in the air above. Winds blowing at between 10 and 15 miles per hour over InSight’s solar panels caused the spacecraft to vibrate, and the spacecraft recorded the vibrations, which were converted into sounds.
The other main instrument on InSight, a heat probe that would hammer itself about 5 meters into the floor of Mars, failed to fully deploy.
Despite two years of efforts, the instrument, nicknamed the “mole”, never got much further than an inch below the surface. The soil where it landed tended to clump, a property unlike any material found elsewhere on Mars. The clumping reduced the surface area of the dirt pressed against the sides of the mole, and with insufficient friction, it was unable to hammer itself down.
“It turned out that the specific soil that was under InSight, when we landed, had a consolidated layer of crusty soil at the very top,” said Dr. banerdt. “And that crust, the ground kind of fell apart as the mole tried to get in.”
Without the mole that made it underground, the scientists haven’t obtained hoped-for measurements of the heat flowing out of the planet, which would have provided more accurate data on Mars’ current internal temperatures and the energy driving geological processes.
“That’s what we lost,” said Dr. banerdt.
Even after InSight goes silent, the possibility remains that a passing dust devil could sweep the solar panels and revive the spacecraft.
“We’ll listen,” Mrs. Garcia said. “And once we get a few beeps, if that happens again, if there’s a natural cleanse, then we’ll evaluate if there’s enough energy to get the lander working again.”