NASA and Intuitive Machines Declare Sideways Moon Lander a Success
“He’s a scrappy little dude.”
In just a few hours, Odysseus — the first U.S.-based craft to land on the Moon in 52 years — will go quietly into the lunar night. It may never wake up again. And its human designers are okay with that.
“No eulogies planned, only celebration and cheering,” Intuitive Machines CEO Steve Altemus said during a press conference on Wednesday afternoon.
Intuitive Machines, the company that built the lander, will power down the spacecraft for the long, frigid lunar polar night around 8pm Eastern Time on Wednesday evening. That was planned all along, and both the company and NASA maintain that — despite an initial communications delay and some broken landing gear that left Odysseus leaning on its hydrogen tank against the side of a low hill — the mission has been a success. Here’s a rundown of why the lander tipped over, what’s coming next, and what fate lies ahead for tipsy Odysseus.
Technically, a good landing — but not a great one
According to Odysseus’s flight computers, the lander is now sitting (or leaning) about a mile short of its planned landing site in a crater called Malapert A. The spot where Odysseus touched down is also on a higher patch of ground than its planned site. Those two things combined meant that the lander was moving faster — both down and forward — than it was supposed to when it touched down.
“We hit harder and sort of skidded along the way,” Altemus said. Images from NASA’s Lunar Reconnaissance Orbiter show churned-up regolith where the lander skidded to a stop. “The landing gear took the bulk of the load, and we broke one or possibly two landing gear,” Altemus continued.
For more than a minute, Odysseus sat upright with its thruster still firing down into the lunar regolith. But as soon as the thruster stopped, the lander began to tip slowly sideways. In the Moon’s weak gravity (about a sixth of Earth’s), the gentle fall took about two seconds. According to Intuitive Machines, the lander came to rest on one of its hydrogen tanks — or possibly a radio shelf — leaning against a shallowly sloping hill. It’s tilted at about a 30-degree angle, which is closer to upright than IM-1’s mission control team initially thought.
Despite the rough landing, the broken gear, and the tilt, both Intuitive Machines and NASA are counting IM-1 as a success. It’s still a “soft landing,” as opposed to a crash (the difference is that the lander survived and kept working, instead of being a bunch of smashed bits of metal on the unforgiving lunar surface).
“The landing gear did what it was supposed to do and protect the lander as it landed on the surface,” says Altemus.
And it appears that all of the IM-1 mission’s payloads have worked as planned. That includes a prototype lunar radio telescope called ROLSES (Radio wave Observation at the Lunar Surface of the photo-Electron Sheath), a receiver designed to measure the background radio “noise” on the Moon. It turns out that at low frequencies (below 15 megahertz), Earth is fairly quiet, but “at the higher frequencies, Earth is shouting out a bit,” says NASA Commerical Lunar Payload project scientist Sue Lederer.
The mission also successfully deployed a laser retroreflector array: a set of precisely-designed mirrors that will act as location markers for future Moon missions.
“We believe that the NASA Lunar Reconnaissance Orbiter is going to be able to use their laser altimeter to range to [the reflectors], so we will be working on that in the coming months,” says Lederer. “We’re very excited to have a location marker on the moon at 80 degrees south. This is going to be great for navigation in the future.”
Meanwhile, NASA plans to send another version of ROLSES and some of its other payloads on future commercial missions — including Intuitive Machines’ IM-2 mission, which is set to launch later this year. The company is already planning a later IM-3 mission as well. And even later missions may feature a larger lander called Nova-D.
“With more cameras,” says Intuitive Machines CTO Tim Crain, laughing. “That message was heard.” (Intuitive Machines caught some flak from the public for a lack of Moon photos during the landing.)
Intuitive Machines’ longer-term plans for the Moon include putting its own communications satellites in lunar orbit.
What Happens to Odysseus Now?
Odysseus was never meant to live past Wednesday evening: Its mission was planned for just 144 hours after landing, when the bitter, machine-killing cold of lunar night will set in.
“This mission was intended as a scout and pilot mission to go land on the surface, collect the data, and then the cold of night was going to take the lander where it would sit there quietly for the rest of time,” said Altemus. “We accomplished that.”
But the IM-1 team plans to try for a little more anyway.
“We expect that within about five hours or so from now, we will be at a point when we will no longer have command or telemetry coming down,” Altemus said at about 3pm Eastern Time. “What we're going to do is try to tuck Odie in for the cold night of the Moon and see if we can't wake him up when we get to solar noon in about 3 weeks.” That means powering down the spacecraft in such a way that its radio and other electronics will switch themselves on when (or if) they start getting power from the solar panels again.
It’s a long shot, as even Altemus and Crain admit. The solar panels will almost certainly weather the lunar night, and when sunlight warms them again, they’ll start sending power to the batteries. And the batteries are the likely problem. The chemistry that makes batteries work does very poorly in extreme cold (as anyone who’s ever tried to jump-start a car in the dead of winter here on Earth can tell you), and so do most other electronic components.
“The batteries absolutely are not tested to that level of cold. Neither is our flight computer or our radios,” says Crain. “If we asked our vendors to tell us what the probability was of surviving the deep cold of the Moon, they would not put it in writing, and well they shouldn't.”
Lederer is more optimistic about Odysseus. “He’s a scrappy little dude,” she says.