NASA’s InSight lander he’s getting ready for his long Martian rest and he’s making us all cry.
In a shocking tweet, the Mars lander social media team shared a dusty image of InSight’s landing site, along with what the laboring space robot might say if it could actually tweet: “My power is very low so this may be the last image I can send. Don’t worry about me though: my time here has been productive and peaceful. If I can continue to talk to my mission team, I will — but I’ll sign off here shortly. Thanks for sticking with me.”
At some point, very soon, a Mars-orbiting satellite will ping InSight for a communications check-in, and the lander will not respond. A few days later, the satellite will try again. when InSight still doesn’t respond, NASA will declare the lander dead. We will not witness the heroic, almost frantic efforts of NASA engineers to restore communications with the Opportunity Rover.
InSight’s human teams have been working for months knowing that any given day’s satellite check-in could be one that InSight simply doesn’t answer.
“It’s like having an old, junk car parked out front. We’re really excited every time it launches, so there’s something to celebrate every week,” says Emily Stough, senior engineer on the InSight operations team at the Jet Propulsion Laboratory. Inverse. “Sometimes, you know, we’re worried about losing the boat, and you know, dust storms and weather, but other times, we’re really excited to keep going and still learn science. “
The robot did its best — The InSight team of engineers and scientists always knew that the lander’s days were numbered. When it crashed into Mars’ equatorial plain in 2018, it was already doomed to suffocate under layers of fine, clinging Martian dust, which would have blocked sunlight from reaching the solar panels that powered it.
“There are probably things that could have been done differently to make the mission last longer. But when we put something like this together, we don’t have an infinite budget,” says InSight project scientist Mark Panning. Inverse. “You really have to think about what science you want to accomplish. What are the questions you want to answer and what measurements do you need to make to answer those questions? And then build a spacecraft that can do that with some cushion. ” And that’s what InSight’s designers did.
Panning says he is often struck by the ideas the public suggests that could have saved InSight from certain doom, from brushes and wipers to air fans to blow away dust — or even making the solar panels with surfaces that look like with hockey tables. But building for space is more complicated and more expensive than people often realize. A brush that costs $2 at a local hardware store could turn into a multimillion-dollar piece of hardware by the time engineers install it on a lander’s robotic arm and run it through a series of tests to make sure it works in every imaginable scenario — and doesn’t break anything else in the process.
“The most efficient thing we could do is make the solar panels much larger than we need, so that we have many times more energy than we need at the start of the mission, but we’re confident that we’ll last long enough to make the measurements we want”. In the end, InSight’s oversized solar panels lasted the main two-year mission — and two years beyond. “This is good engineering,” says Panning.
Good job, InSight — InSight landed on Elysium Planitia, a plain that stretches across the equator of Mars, in November 2018 after a six-and-a-half-month flight from Florida. Over the next four years, the lander’s instruments recorded more than 1,300 Marsquakes, while other instruments on board measured Martian weather and the ragged remnants of the planet’s magnetic field.
InSight revealed that Mars is a much more volatile world than expected, but its frequent thunderstorms are mostly small. the largest earthquake ever recorded, in early May 2022, had a magnitude of 5.0. Here on Earth, that’s the kind of thing people in seismic areas tend to shrug off, but for future Mars explorers, it could be a bigger safety hazard.
“If you’re in an environment where you’re trying to maintain an atmosphere that’s habitable while the rest of the world around you isn’t, things falling down is pretty bad,” says Panning.
By using the timing of seismic waves moving through the ground, Panning and his colleagues were able to accomplish one of their primary goals for the mission: mapping the interior depths of Mars’ crust, mantle, and core.
The only thing InSight failed to do was measure the heat flow inside the planet, which could give scientists clues about the energy behind all that wobble. The thermal probe, or mole, was meant to collect data from a vantage point about 3 meters (10 feet) below the surface, but despite two years of effort — and literally trying to hammer the mole into the ground with InSight’s robotic arm — InSight managed to bury the instrument only a few centimeters in the Martian regolith.
“When we started hammering, it just didn’t go anywhere,” Stough says.
Keep as much as possible — The robotic arm came in handy in another unexpected way in 2020, when Mars was at its farthest from the Sun and the light reaching InSight’s solar panels was dimmer than usual.
“One of our scientists had a theory that if we use our scoop to pick up some of the regolith on the ground and drop it next to our solar panels while the wind is blowing, the wind might blow some larger particles into the solar arrays, which they’ll kind of excite the smaller, dusty, light ones in the air so that the wind will carry them along,” says Stough. “It seems like a really crazy idea, but so many things in science and engineering are, you’re hearing them for the first time. And we tried it, and it really worked.”
The maneuver worked well enough to give InSight a boost of 30 watt-hours, enough to run the seismometer for eight hours. But subsequent efforts were less successful, and it soon became clear that the stopgap measure could not hold the ground forever.
In the summer of 2022, with power output down to 20%, the InSight science team decided to shut down most of the lander’s instruments: wind sensors, pressure sensors, magnetometer, and radiometer. Instead, every bit of remaining power would be dedicated to InSight’s seismometer — which would operate for just a few hours during the quietest part of the Martian day. The team also disabled a fail-safe system that was supposed to safely shut down the lander if its power got too low.
And that straight-to-the-bitter approach has worked for the past several months. By November 2022, with InSight’s fourth anniversary on Mars approaching, the spacecraft was generating just 10 percent of the power it had at the start of its mission.
The end is near – Now, as 2022 draws to a close, the InSight team awaits the inevitable end.
“We’ll wait for a downlink, but we won’t get a downlink,” says Stough. “We’ll probably double-check with all the ground teams to make sure there’s actually no data, we’ll check with the orbiters, we’ll check with the Deep Space Network, we’ll look everywhere for that data before we say, ‘okay, we missed the pass. ». And then we hold our breath for a few days while we wait for the next one.”
InSight has made a few calls to its Earthbound counterparts before, so they’ll wait for a second missed communication window before declaring the mission complete — and even then, they won’t completely give up hope.
“InSight was designed to wake up again if the batteries can be recharged. So there’s a chance, albeit a small one, that we’ll hear it again,” says Stough. The Deep Space Network’s long-range radio antennas will be heard occasionally for years to come, just in case a highly unlikely gust of wind happens to blow the dust off InSight’s solar panels and revive the craft.
But once the mission is over, Stough and her operations team will move on to other projects. Many already split their time between InSight and other missions, such as the Perseverance rover. And for Panning and the other scientists, the work will continue long after InSight goes quiet.
His team is adding InSight’s science data to NASA’s Planetary Data System, as well as an archive managed by the Incorporated Research Institutions for Seismology. In both places, InSight’s Marsquake measurements will be accessible to researchers around the world. Along with earthquake data from the Apollo missions, InSight provided one of only two sets of alien seismic data ever recorded.
“We still have a lot of science to do,” says Panning.