Intuitive Machines landed on the moon!!...sideways

On Thursday, February 22, Intuitive Machines successfully landed a Nova-C lander, called Odysseus, on the moon. This is the first successful private moon landing ever, and the first U.S. spacecraft to successfully soft land on the moon since the end of the Apollo program.

Here’s what happened, and everything we still don’t know about the landing.

Why the landing time kept changing leading up to the launch

The landing was originally scheduled the landing for 5:49 PM ET, but it changed multiple times throughout the day.

It wasn’t clear exactly why at first — it moved earlier, to 4:30 PM, then earlier again. Then finally, Intuitive Machines delayed the landing to later, 6:24 PM ET, which stuck.

It turns out Odysseus actually entered the moon in an elliptical orbit on February 21st. The team had to perform a correction maneuver to put the spacecraft in a circular orbit, which was successful, but it’s what moved the landing time earlier.

Then, more trouble: The laser range finders on the spacecraft weren’t working.

These are crucial for landing. Much of the landing process was automated, and these laser range finders provide information to the landers navigation algorithms. They’re important for control and guidance during descent, so as you can imagine the spacecraft can’t land without them.

(We found out at the press conference that the laser range finders weren’t working because it turns out someone forgot to enable the safety switch for the lasers. They require safety switches because they’re not eye safe. The safety enable switch was in the box and was not disabled.)

But some quick thinking solved the problem: As I mentioned in my previous video about the mission, Odysseus is carrying an experiment with NASA LIDAR aboard.

It’s called the Navigation Doppler Lidar for Precise Velocity and Range Sensing, and it’s a guidance system designed to measure altitude, direction, and speed during landing.

The system wasn’t supposed to be mission critical, the intention was just to test the system on the lunar surface. But it turned out to be crucial to Odysseus’s successful landing.

With time running out, the engineers at Intuitive Machines wrote a patch that would allow the spacecraft to use NASA’s LIDAR system instead of its own, uploaded it to the spacecraft, and waited to see if it would work. It DID, and then they were able to proceed with the landing.

But that’s why the landing time got pushed back a couple of hours, they allowed Odysseus an extra orbit of the moon to give Intuitive Machines time to troubleshoot the problem and find the fix.

This was a nail-biter for sure

Odysseus entered powered descent about 10 minutes before the scheduled landing time.

Everything was fully automated at this point; the team at Intuitive Machines knew that there might be drops in communication, so they configured the spacecraft to handle exactly what it needed to do locally. The team, and those of us watching at home, were just along for the ride.

Everyone knew that at this point, the spacecraft would land — it was just a question of whether it’d be the planned soft landing or a crash into the lunar surface. The landing time came and went, and while we knew that there would be a delay before the team got confirmation of the landing, it was much longer than the 15 seconds we’d been told.

The Mission Director, Tim Crain, said “It may take a minute for comms to re-establish.”

One minute passed, then two. No word from Odysseus.

Odysseus: Out of contact or destroyed on impact?

The team over at Intuitive Machines began working the issue as a communications problem. They assumed that Odysseus had indeed soft landed successfully on the moon, but was having trouble getting a signal back to Earth.

If Odysseus was intact, but didn’t have communications with Mission Control, it was designed to power cycle every 15 minutes and switch to a new dish location until it regained contact.

Usually space missions use the Deep Space Network, which is NASA’s giant array of radio antennas located in Madrid, Spain; Goldstone, California; and Canberra, Australia. This is operated by NASA’s Jet Propulsion Laboratory, but it basically supports communication with all spacecraft outside of Earth orbit, no matter the country.

Except Intuitive Machines is doing something different. They’re using their new network for communication: the Commercial Lunar Data Network. It’s a private communication network specifically for lunar missions, developed by Intuitive Machines. It has ground stations across the world, including in the UK and Australia, as well as five data relay satellites in orbit of the moon. While it was tested during, and successfully tracked, NASA’s Artemis I mission, it’s still new.

As Intuitive Machines worked what they presumed was a comms issue, they were trying to make sure antennas were in direct line of sight with their network of ground stations on Earth, as well as pointing a dish in the UK towards what they thought was their final landing site. Part of this mission is testing the robustness of the Commercial Lunar Data Network and working out the kinks.

But the good news is everything worked the way it was supposed to.

Confirmation: The soft landing was successful

About 10 minutes after the expected landing time, Mission Control announced that they’d detected a faint signal from Odysseus’s high-gain antenna. At that point, as the team worked to boost the signal, the mission director confirmed that the team had achieved a successful landing on the moon.

“Houston, Odysseus has found his new home.”

It might have seemed a little premature, but the reasoning is basically that if the craft hadn’t soft landed, if it had crashed into the moon, then there would be no signal. This meant that Odysseus was intact on the lunar surface.

At 8:25 PM ET on Thursday, Intuitive Machines confirmed that they were in contact with Odysseus and it’s sending back data.

The spacecraft is solar charging successfully, and it does have good telemetry, which means it’s communicating information. We’re still getting information on its precise location.

Intuitive Machines shared this photo which was taken during descent. It’s about 10 km above the surface of the moon, about 200 km from the landing site, but it shows us just how difficult the surface is around the landing site — which will make what I’m about to say next less of a surprise.

What’s interesting is that while Intuitive Machines did confirm previously that the spacecraft was upright. BUT. It’s actually tipped over on its side. The lander touched down at 6 miles per hour vertical speed, but its horizontal speed was 2 miles per hour, so one of the legs might have gotten caught.

At the press conference, Steve Altemus, CEO and co-founder of Intuitive Machines, showed us exactly what attitude they think the lander is at. Initially, they thought it was upright because the tanks were reading gravity in the tanks. But overnight, they realized the spacecraft actually tipped over. Again, this doesn’t seem to be a huge deal, they confirmed that the experiments are working properly, but we’ll see if it has a lasting effect.

Here’s what happens next

So, what’s next for Odysseus? We’re still getting information on its precise location but the spacecraft appears to be healthy. Tim Crain, who was the Mission Director and also is Intuitive Machines’ Chief Technology Officer, said that the vehicle performed flawlessly. They’re still working on downloading images, which is what I’m really looking forward to.

What I’m really looking forward to is the images. On its way down, Odysseus basically threw a camera called Eagle Cam outside during descent, in hopes that the tiny Cubesat camera system would take pictures during descent. We’ll see if that worked.

The spacecraft has about one week of lunar day (remember days on the moon are two weeks long) to conduct science, so we’ll keep getting updates. But this is a huge achievement for Intuitive Machines and I’m so excited it was successful.