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Odysseus is on its side, some antennas blocked

It appears the reason communications with Intuitive Machines’ Odysseus lunar lander has been so difficult since its landing yesterdary is that something caused it to fall over so that it is now lying on its side, blocking some of its antennas.

Intuitive Machines initially believed its six-footed lander, Odysseus, was upright after Thursday’s touchdown. But CEO Steve Altemus said Friday the craft “caught a foot in the surface,” falling onto its side and, quite possibly, leaning against a rock. He said it was coming in too fast and may have snapped a leg. “So far, we have quite a bit of operational capability even though we’re tipped over,” he told reporters.

But some antennas were pointed toward the surface, limiting flight controllers’ ability to get data down, Altemus said. The antennas were stationed high on the 14-foot (4.3-meter) lander to facilitate communications at the hilly, cratered and shadowed south polar region.

Its exact location also appears to be several miles from its intended landing site next to the crater Malapart A. Scientists who operate Lunar Reconnaissance Orbiter (LRO) hope orbital images this weekend will identify the spacecraft’s precise location.

The company also revealed that the reason its own laser guidance system would not function — requiring a quick software patch allowing the spacecraft to use a different NASA system — was because “a switch was not flipped before flight.”

Because of this switch in navigation equipment it was decided to cancel the release of the student-built camera probe dubbed Eaglecam that was supposed to be released when Odysseus was about 100 feet above the surface and take images of the landing. Instead, it is now hoped it can be released post landing and get far enough away to look back and capture photos of the lander.

All these problems however do not make this mission a failure. Like Japan’s SLIM lander, the primary goal of this mission was to demonstrate the technology for softlanding an unmanned spacecraft on the Moon. Intuitive Machines has succeeded in this goal. Though obviously some changes must be made to improve this engineering, the success with Odysseus strongly suggests the next mission later this year will do far better.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.

The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News


  • Questioner

    Congratulations on almost a successful landing. It is also astonishing that a NASA navigation experiment that was not actually intended to have an operational role saved the mission and made the landing possible at all.

    Mr. Zimmerman: When I speak of NASA, we should not hide their enormous contribution to this project. No, it’s not about financing the actual lunar landing mission, but also about the development of essential technologies such as the cryogenic rocket engine (CH4+LOX) and the advanced navigation system, in collaboration with various companies, but essentially led and carried out by NASA itself. First and foremost, the Morpheus lander project should be mentioned here.

    I would therefore not like to call this Odysseus-lander and the associated overall project a private venture, but rather a public-private collaboration.

  • wayne

    N.A.S.A.’s Ranger Program
    RetroRockets (May 2021)

  • MDN

    That the navigation system ended up being a trivial stage 0 countdown mistake is excellent news as it is easy to fix and bodes well that the next mission can proceed ASAP.

    WRT the error itself it is disappointing, but not surprising. The nav lasers are no doubt hardwire disabled during pre-flight handling because they must represent an EXTREME risk of permanent eye injury if activated accidentally as they are basically laser pointers on steroids. So disabling them like this is little different than the padlock circuit breaker cutoff used on high voltage electrical systems because you REALLY want to obviate stupid serious injury risk because people make mistakes..

    As this was their first mission it is not surprising a subtle detail like this got overlooked. But I still wouldn’t want it on my resume. One would think that validating the operation of ALL critical systems prior to launch would be the standard, but as I said people make mistakes.

  • wayne

    A legitimate question (with only a bit of snark):
    Can I make the assumption Intuitive Machines built more than one of these landers, and #2 is ready to go with upgrades?
    Talk about putting all your eggs in one basket… (they apparently tip over.)

    If Musk was running this show I’d wager he’d have 10 of these crash spectacularly into the Moon, until he got it right, and then do it perfectly for so long we’d forget it was ever any other way.
    (and besides, we’ve done this all before…what’s the real problem?)

    Soil Sampler Sequence (1967)
    Retro Space (May, 2019)
    “The television camera on Surveyor 3 consisted of a vidicon tube. The camera returned 6315 pictures between April 20 and May 3, 1967, including views of the spacecraft itself, panoramic lunar surveys, views of the mechanical surface digger at work, and of an April 24 eclipse of the Sun by the Earth.”

  • Ray Van Dune

    I wonder to what extent the lack of GPS on the Moon has contributed to the landing problem? Both the recent Japanese lander and now the U.S. lander have apparently suffered from the same problem – a lack of ability to negate lateral motion at the terminal descent.

    Vertical control can be achieved in a relatively straightforward manner by radar or lidar, but lateral control requires more sophisticated ranging or image processing with the integration of data from multiple sensors. I believe Falcon 9 horizontal landing control is achieved through GPS by the booster and by controlling the landing barge position if required.

  • Ray Van Dune

    Ps. It should be asked: could a receiver in lunar space use the Earth constellation of GPS satellites to determine its position?

    Obviously there would be non-trivial technical challenges, but assuming the requisite enhanced signal sensitivity could be achieved, much of the GPS position data is derived from relative signal timing, a parameter that could be largely distance-insensitive!

  • Ray Van Dune, interesting question about the GPS system being used from the moon. I’m not an expert, and I totally acknowledge that earth satellites have used GPS receivers to calculate their positions in orbit. But I could see a few potential issues:

    1. Distance differential issues: GPS works by measuring the timing difference between satellites, since the moon is ~226 K miles vs 12.5 K miles, or ~18 times farther away, which would I believe increase the odds that the timing differences between the satellites would be reduced.
    2. Antenna pattern: Most of the GPS energy is pointed at the ground, satellites that use GPS for navigation from above the GPS orbital path seem to use the leakage from satellites passing around the side of the globe. I found an article about it here: but I wonder if the signal would be strong enough to be reliably heard from the moon?

    Having said all of that though, a moon based GPS type system would be extremely useful. If that was coupled with a meshed data link system like Starlink that linked to either a commercial version of the Deep Space Network, or the Deep Space Network then moon experimenters could benefit from using cheaper lower power antennas on the moon to move data…

  • Richard M


    “Can I make the assumption Intuitive Machines built more than one of these landers, and #2 is ready to go with upgrades?”

    Pretty close. Intuitive Machines has three missions contracted through NASA’s CLPS program, and the second one, also a Nova-C lander (IM-2), is scheduled for fourth quarter of this year. It will, in fact, have a drill (PRIME-1) combined with a mass spectrometer, to attempt harvesting ice from below the surface. There is a third Nova-C lander (IM-3) scheduled for launch early next year. As I understand it, these vehicles are largely fabricated now.

    That said, given that this was not a problem free mission, it is hard to tell if the investigation(s) into those problems, and any resulting changes, will push pack those missions.

    What does worry me is their finances. I don’t think they have ever turned a quarterly profit, and their cash on hand is limited. I do think they need to rack up a more complete success on these next two landers to assure a healthy future.

  • wayne

    Thanks for the factoids. I don’t follow this very closely.

  • With respect to GPS and communications, I thought I heard something said during the lengthened landing video stream that there was a package on board that would provide some information for eventually developing Lunar GPS and communications systems for landers that were on the side away from the Earth or just in difficult positions to “phone home”. One thing that will have to be addressed is providing power to a lander during Lunar night.

  • pzatchok

    Could a bunch of quick cheap GPS sats be built and then launched on a Falcon to orbit the moon?

    Pretty much all they need to do is get a Falcon second stage into lunar orbit and then deploy them.
    They could use already existing lunar lander’s as primary guides to help them get into the proper orbit.

    They should use a different GPS frequencies so there is no possible way to interfere with Earth systems.

    I bet it could be done pretty cheap though.

  • Call Me Ishmael

    “Could a bunch of quick cheap GPS sats be built and then launched on a Falcon to orbit the moon?”

    They wouldn’t stay in orbit. There are basically no stable lunar orbits, due to the effects of the Sun, the Earth, and lunar mascons.

  • pawn

    The navigational issues in lunar orbit and on the surface are being studied right now. I believe the Lunar Gateway and the LRO are going to have a role in a barebones RF navigational system. There are contracts and papers out on this.

  • Patrick Underwood

    The lunar orbit situation is complicated.

    SpaceX will have to tackle this nav/comms problem at Mars to fulfill their company-defining goal. They have the satellite technology to do it. I’m surprised they haven’t stated an interest in creating a lunar nav/comms constellation (“StarLune”). I believe other companies have done so, maybe even Intuitive Machines? Whoever fields it will be in the happy position of selling shovels and blue jeans to miners…

  • Jerry Greenwood

    “a switch was not flipped before flight.”

    What ever happened to check lists?

  • Ray Van Dune

    “What ever happened to check lists?”

    That was my first thought! Then I remembered that this lander used cryogenic rocket propellants that tend to boil off, so the lander had to be fueled on the launchpad at the same time as to booster. Normally a space probe uses hypergolics and can be sealed up in a clean-room, shipped to the launch site, and never touched again.

    I’ll bet they had to disable all sorts of systems to access this probe on the pad and fill it up! This would be outside of normal procedures at the launch site, and I’ll bet they just didn’t have to the disciplines there (as opposed to at the systems integration lab) to make absolute sure that they turned everything back on!

  • Formerly known as Skeptic

    What ever happened to “Remove Before Flight” tags? If there was a prominent red streamer attached to or near the switch, even if someone borked up the checklist, it would be hard to miss.

  • Joe

    pzatchok – We have been studying GPS like systems for the Moon, Mars, etc. It is not a simple problem but advances in equipment would make building these fairly inexpensively. The hard part would be the launches needed to spread them out orbitally. You need several orbital planes for ir to work. That means multiple launches.

  • Doubting Thomas

    No pictures yet. I wonder if the software fix to the automatic antenna pair switching is taking longer than expected or not working the way they thought?

    Same thought about the Laser Radar – “Remove Before Flight” & Checklists.

    Apparently, the turn on protocol was to prevent eye hazard issues. It seems like an accelerometer & fairing separation sensor combination would have worked if they lacked the discipline to read the check list and flip a ground switch.

  • Richard M

    In related news… JAXA’s SLIM apparently survived the lunar night! JAXA is in communication with it now. They started receiving telemetry from SLIM around 5:00 a.m. Eastern (1000 UTC).

  • Richard M


    “Then I remembered that this lander used cryogenic rocket propellants that tend to boil off, so the lander had to be fueled on the launchpad at the same time as to booster. Normally a space probe uses hypergolics and can be sealed up in a clean-room, shipped to the launch site, and never touched again. I’ll bet they had to disable all sorts of systems to access this probe on the pad and fill it up!”

    Great point. It doesn’t get made very often in these pile-ons on Intuitive Machines staff.

    It is still a failure, one they must address for future missions. But it is easier to see how it could have happened. It’s not a complication that previous lunar landing missions have had to deal with.

  • Edward

    February 25, 2024 at 12:57 pm
    Jerry Greenwood asked: “What ever happened to check lists?

    Ray Van Dune sort of answered: “I’ll bet they had to disable all sorts of systems to access this probe on the pad and fill it up!

    I have written more than my fair share of procedures, and I learned early on that if you are going to turn off a switch (or take something off, etc.) then write the step that turns it back on before writing the step to turn it off.
    On the topic of GPS, keep in mind that we have successfully landed many probes on the Moon and on Mars without GPS-like systems. We even landed Apollo 12 right next to a Surveyor unmanned probe. We don’t need GPS to successfully land on other worlds.

  • pzatchok

    the GPS sats could also be communication relays to ensure Earth communication from all around the Moon.

    If those very same sats could stay in orbit around the Earth for many years how long would they stay in Lunar orbit? They could be used at a higher altitude relative to the Starlinks on Earth.

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