Intuitive Machines' Odysseus lander tipped over on the moon during 'spicy' lunar landing

The private Odysseus lander is down on the lunar surface, in more ways than one.

The 14-foot-tall (4.3 meters) Odysseus, which was built by Houston company Intuitive Machines, apparently settled on its side during its historic touchdown yesterday (Feb. 22), mission team members said. But don't panic — the pioneering spacecraft is still very much alive.

"So far, we have quite a bit of operational capability even though we're tipped over," Intuitive Machines CEO and co-founder Steve Altemus said during a press briefing today (Feb. 23). 

"And so that's really exciting for us, and we're continuing the surface operations mission as a result of it," he added.

Related: Intuitive Machines lands on moon in nail-biting descent of private Odysseus lander, a 1st for US since 1972

Artist's illustration of Intuitive Machines' Odysseus lander on the moon in the planned configuration, compared with its apparent actual configuration (inset, demonstrated with a model during a press briefing on Feb. 23, 2024). (Image credit: NASA TV)

Odysseus launched on Feb. 15 atop a SpaceX Falcon 9 rocket, carrying six NASA science instruments and six private payloads toward the moon. The lander arrived in lunar orbit six days later and touched down yesterday evening, about 190 miles (300 kilometers) from the moon's south pole.

It was the first successful lunar landing by an American vehicle since the end of the Apollo era in 1972, and the first-ever by a private spacecraft.

And it took some quick thinking by the mission team to pull it off. 

As the target landing time neared yesterday, Odysseus' handlers realized that its laser rangefinders weren't working properly. So they implemented a workaround to get the required altitude and velocity data, pressing into service an experimental NASA instrument aboard Odysseus called NDL ("Navigation Doppler Lidar for Precise Velocity and Range Sensing)."

The team delayed the planned touchdown by two hours to make the fix, which required them to beam a software patch to Odysseus from mission control in Houston.

"It was quite a spicy seven-day mission to get to the moon," Altemus said today.

The landing came with a little extra dash of flavor as well, the team announced today. While they're still analyzing data, it's pretty clear that Odysseus didn't land vertically as intended, Altemus and Tim Crain, Intuitive Machines co-founder and CTO, said during today's briefing.

During its final descent, Odysseus was supposed to be traveling about 2 mph (3.2 kph) in the vertical direction and 0 mph horizontally. But the data show it was actually moving at roughly 6 mph (10 kph) vertically and 2 mph (3.2 kph) horizontally, Altemus said.

He offered a theory about what happened: Perhaps, while coming down at those slightly off-nominal speeds, Odysseus caught one of its landing legs in a crevice or other piece of lunar terrain. 

As a result, "we might have fractured that landing gear and tipped over gently," he said.

More data are needed before the team can make a full assessment. Some particularly revealing information could come from another payload aboard Odysseus: EagleCam, a system built by students at Embry-Riddle Aeronautical University that was supposed to deploy from the lander during its descent and photograph the touchdown from the lunar surface.

The mission team decided to keep EagleCam aboard during landing, however, due to the navigational difficulties. It's still on the spacecraft, but the team plans to deploy it soon, hopefully getting some good ground-level shots of Odysseus as it now lies.

Like EagleCam, Odysseus' other instruments and important subsystems appear to be functional, Altemus said.

"We have the sun impinging on the solar arrays and charging our batteries," he said. "We are providing power to the spacecraft, and we're at 100% state of charge. That's fantastic."

The data suggest that Odysseus came down within a mile or two of its target landing zone, a patch of relatively flat ground near a crater called Malapert A, Altemus added. The precise touchdown spot could soon become clear; NASA's Lunar Reconnaissance Orbiter will snap photos of the area from above this weekend, if all goes according to plan.

The mission team will gather, and beam home, as much data as they can from Odysseus' new home on the moon. But the lander's electronics were not designed to survive the harsh cold of lunar night, so its days are numbered.

"We know at this landing site, the sun will move beyond our solar arrays, in any configuration, in approximately nine days," Crain said. "The best case scenario, we're looking at another nine to 10 days."

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Mike Wall
Senior Space Writer

Michael Wall is a Senior Space Writer with Space.com and joined the team in 2010. He primarily covers exoplanets, spaceflight and military space, but has been known to dabble in the space art beat. His book about the search for alien life, "Out There," was published on Nov. 13, 2018. Before becoming a science writer, Michael worked as a herpetologist and wildlife biologist. He has a Ph.D. in evolutionary biology from the University of Sydney, Australia, a bachelor's degree from the University of Arizona, and a graduate certificate in science writing from the University of California, Santa Cruz. To find out what his latest project is, you can follow Michael on Twitter.

  • geek55105
    It wouldn't be that hard to design a spacecraft that could handle a tip-over event, assuming the main retro-rockets slowed it down enough to make a mostly soft landing. Add some extra "legs" all around it, give all legs controls to lengthen or contract, make sure every part can handle being upside down, and Bob's your uncle (as the Brits say). I believe the Japanese lander has a small remote explorer designed like that. Why isn't this given more consideration for robotic missions?
    Reply
  • DirtyBearDog
    geek55105 said:
    It wouldn't be that hard to design a spacecraft that could handle a tip-over event, assuming the main retro-rockets slowed it down enough to make a mostly soft landing. Add some extra "legs" all around it, give all legs controls to lengthen or contract, make sure every part can handle being upside down, and Bob's your uncle (as the Brits say). I believe the Japanese lander has a small remote explorer designed like that. Why isn't this given more consideration for robotic missions?
    I’m sure nobody thought of such a smart idea. Given the infinite budget, time to design and test, but especially the mandate that none of these missions have any problems, this was a huge misstep. Thankfully you’ve spotted it and they will correct it for the next mission that will also bear no resemblance to the parameters I’ve listed above. I’m sure a thank you card and cake is on its way right now.
    Reply
  • Unclear Engineer
    From that other space site's reporting:

    "Controllers discovered the problem with the lander’s laser rangefinders after going into orbit around the moon Feb. 21 and deciding to use them to more precisely measure the lander’s orbit, which was more elliptical than intended. The lasers, though, did not work, and engineers determined that a physical switch — a safety measure on the ground because the lasers are not eye-safe — was not flipped before launch."
    So that is why the NASA LIDAR system data was quickly patched into the landing software. I am wondering if that had anything to do with the off-nominal performance of the landing itself.

    But, more importantly, wasn't there a pre-launch checklist with a box to check for flipping that eye safety switch to the correct position? And wasn't there a box to check by some supervisor that says (s)he reviewed that check list and determined that all of the boxes had been checked?

    I am getting concerned that our aerospace industry has lost a lot of its safety/reliability culture. With doors falling off airplanes in-flight, and the Peregrin Lander having a fatal fuel leak, and now the Odysseus lander having a switch not thrown, I am wondering why we are not seeing better testing for reliability purposes.

    With the New Glenn rocket's scheduled first flight, it is already going to carry NASA payloads. Shouldn't it have to at least get off the pad once before we start betting payloads on it?
    Reply
  • Unclear Engineer
    geek55105 said:
    It wouldn't be that hard to design a spacecraft that could handle a tip-over event, assuming the main retro-rockets slowed it down enough to make a mostly soft landing. Add some extra "legs" all around it, give all legs controls to lengthen or contract, make sure every part can handle being upside down, and Bob's your uncle (as the Brits say). I believe the Japanese lander has a small remote explorer designed like that. Why isn't this given more consideration for robotic missions?
    This lander already had 6 landing legs. The thinking at the moment is that the 1 m/sec horizontal velocity might have caused one of those legs to catch on a surface irregularity and "trip" the lander onto its side as it touched down.

    If that is the case, it would be difficult to design a leg system that could both survive the effects of the sideways impact and then function well enough to right the lander to vertical position no matter what orientation it settled into.

    And, that does not deal with any instrument package damage that could occur with the lander hitting the surface on its side.

    So, I think it is better to work on the landing process reliability than try to make a craft so robust that it could handle any sort of landing problem without damage. Such a robust craft would clearly have to weigh more and have a lot more energy storage capacity than most landers are designed with.

    But, that said, when we start putting astronauts on this type of lander, there clearly should be a "Plan B" for problems with the lift-off mode for their craft. Even a "Plan C" still seems like a good idea to me. And those will cost serious money.
    Reply
  • Sadot
    Admin said:
    Intuitive Machines' Odysseus moon lander apparently settled on its side during its historic Feb. 22 touchdown, but the spacecraft remains operational on the lunar surface.

    Intuitive Machines' Odysseus lander tipped over on the moon during 'spicy' lunar landing : Read more
    Sorry this is not historic... if it is historic then so was Japan's, India's , Russia's attempt , israel's and so on...
    If we are considering success and failure being equal. It's the everyone gets a trophy scenario.
    If this thing is on it's side \(yesterday they said it was upright) and not in a million pieces then . Someone needs to be fired for failing to turn on the switch.
    Reply
  • Unclear Engineer
    Well, we can argue about the meaning of "historic", because even failures are part of "history". And that is probably the reason that so many of these rah-rah publicity statements use that term instead of something like "unqualified success".

    But, the reality is that these missions with imperfect landings are partial successes in the development of lunar landing technologies. They showed improvements, so were partially successful, even though they did not meet all of their design objectives. In that sense, there were notable achievements involved. And probably some lessons learned the hard way.

    The Odysseus mission is particularly notable in that it was largely a commercial enterprise instead of a government enterprise, starting at the launch pad. However, if it had not been for the inclusion of the NASA package that was programmed into the landing process during the last hour to replace a failed commercial sensor, the mission would have been called another failure.

    As I said in a previous post, I do not understand how a proper execution of a proper prelaunch process missed flipping that switch. Is that something that commercial companies still need to learn?
    Reply
  • Sadot
    Unclear Engineer said:
    Well, we can argue about the meaning of "historic", because even failures are part of "history". And that is probably the reason that so many of these rah-rah publicity statements use that term instead of something like "unqualified success".

    But, the reality is that these missions with imperfect landings are partial successes in the development of lunar landing technologies. They showed improvements, so were partially successful, even though they did not meet all of their design objectives. In that sense, there were notable achievements involved. And probably some lessons learned the hard way.

    The Odysseus mission is particularly notable in that it was largely a commercial enterprise instead of a government enterprise, starting at the launch pad. However, if it had not been for the inclusion of the NASA package that was programmed into the landing process during the last hour to replace a failed commercial sensor, the mission would have been called another failure.

    As I said in a previous post, I do not understand how a proper execution of a proper prelaunch process missed flipping that switch. Is that something that commercial companies still need to learn?
    Yeah you are correct... this most likely the start of a good thing. As for the other thing... check list are important. I honestly think the only way man will get to another planet is if we all work together. Can you imagine how much we could do if all space capable nations worked together . We would be Star Trek'n for sure! Take care
    Reply
  • Unclear Engineer
    "Working together" has had its successes and failures.

    It looks to me like the main driver of human technological successes has been their values to competition among different factions of humans. Technological advances at this stage in our development of human societies require enormous amounts of money and talent to be applied in a focused manner on objectives identified as being beneficial to the society in some way. Because of our proclivity to engage in wars, technological advancements are mostly seen as enhancing national security, even when they do not directly address things like weapons development or energy independence.

    So, I have to wonder whether we would have much technology at all if we all got along well together and only had pure curiosity to induce us to work on advancing our understanding and capabilities.
    Reply
  • Sadot
    Unclear Engineer said:
    "Working together" has had its successes and failures.

    It looks to me like the main driver of human technological successes has been their values to competition among different factions of humans. Technological advances at this stage in our development of human societies require enormous amounts of money and talent to be applied in a focused manner on objectives identified as being beneficial to the society in some way. Because of our proclivity to engage in wars, technological advancements are mostly seen as enhancing national security, even when they do not directly address things like weapons development or energy independence.

    So, I have to wonder whether we would have much technology at all if we all got along well together and only had pure curiosity to induce us to work on advancing our understanding and capabilities.
    Dang... that last part was deep! You are on to something ! Be Well.
    Reply