A day after its historic landing, the first private spacecraft on the moon is in good condition but has tipped over, the company that built it said Friday.
The spacecraft, named Odysseus, crashed into the moon’s south pole region Thursday night, the first American vehicle to land softly on the moon since Apollo 17 in 1972.
“The vehicle is stable near or at our intended landing site,” Steve Altemus, the CEO of Intuitive Machines, said during a NASA press conference on Friday. “We have communications with the ground.
He added: “This is amazing to begin with.”
But the landing did not go well. Because the spacecraft crashed, its antennas are not pointed directly at Earth, limiting the amount of information that can go back and forth.
Ulysses has not sent back any photos from the landing, although Mr. Altemus showed one taken while the spacecraft was surfacing. “You see how shady and undulating the ground is,” he said.
Engineers at Intuitive Machines are still trying to extract more information from the spacecraft.
Mr. Altemus and Tim Crain, the chief technology officer, also described unforeseen malfunctions that nearly doomed the mission. The landing was saved by calm and frantic work, they said.
When Ulysses reached the moon on Wednesday, it was supposed to enter a circular orbit about 62 miles above the surface. But due to inaccuracies in its orbit, the spacecraft ended up in an elliptical orbit. An additional engine burn put Ulysses on a better trajectory.
To check how close the spacecraft was getting to the surface of the Moon, flight controllers activated the laser beam finders, instruments that could measure the height of the spacecraft upon landing by firing laser pulses at the surface of the Moon.
But when controllers checked the data the next morning — just hours before Thursday’s scheduled landing — they discovered that a laser had not fired. It was then discovered that the safety switches on the two ranging lasers were still on when Ulysses went into space.
There was no way to flip the switches—they couldn’t be overridden via software—now that the spacecraft was more than 200,000 miles away.
“I can laugh about it now,” Mr. Altemus said at the news conference.
“Tim was at the console as the mission manager and I said, ‘Tim, we’re going to have to land without a laser range,'” he said. “And his face went completely white, because it was like a punch in the stomach, that we were going to lose the mission.”
They were looking for possible solutions when Dr. Crane realized that Odysseus actually had a handy backup.
It also carried an experimental instrument called the Navigation Doppler Lidar that NASA wanted to test—essentially a more sophisticated instrument with three laser beams that measure not only the height but the speed of the spacecraft as it descends.
This instrument could provide the missing readings.
“It sounds easy in hindsight,” said Dr. Crane. All the engineers had to do was patch the spacecraft’s software in order for NASA’s instrument to provide its readings to the guidance, navigation and control computer.
“In normal software development for a spacecraft, this is the kind of thing that would take a month,” said Dr. Crane. “Our team basically did it in an hour and a half.”
That Odysseus reached the moon in the wrong orbit turned out to be lucky. Without the need for trajectory control, the laser altimeter would not have been activated until an hour before landing. At that point, it would be too late to find a solution to the locked probes, and Ulysses would almost certainly have crashed.
“We probably would have been five minutes into landing before we realized those lasers weren’t working if we hadn’t had that fortuitous event,” said Dr. Crane. “So serendipity is absolutely the right word.”
There was one more problem.
Installing the software changes on the Odysseus required a reboot of the onboard computer. An attempt to do this in a sophisticated test simulation showed that the spacecraft would drift off course. So the controllers had to find a way to restart the computer without dooming the spacecraft.
“We had to work feverishly,” Mr. Altemus said. “That’s what made us all bite our nails a little bit.”
The extra orbit added two hours to finish.
The jury-rigged navigation software worked.
However, something went wrong as the spaceship landed. The craft was descending faster than expected and was still moving sideways at two miles an hour when the motion should have been completely vertical.
One of the six landing legs may have caught the surface, overturning the spacecraft. “We might have broken the landing gear and flipped gently,” Mr Altemus said.
A Japanese spacecraft also capsized during the moon landing in January. That spacecraft, known as the Smart Lander for Investigating Moon, or SLIM, was also operational after it fell.
Engineers at Intuitive Machines are still working to speed up communications with Ulysses and determine what science tasks can still be performed. This includes a small camera system built by students at Embry-Riddle Aeronautical University in Daytona Beach, Fla., which is supposed to launch when Ulysses was about 100 feet above the ground and capture photos of the landing.
There wasn’t enough time to include camera deployment in the patched landing software, so it remains attached to Ulysses. But Mr Altemus said Ulysses might still be able to get the camera out, which could then take some pictures of the area.
Ulysses’ mission is likely to be over by next weekend. “We know that at this landing point the sun will move past our solar arrays, in any configuration, in about nine days,” said Dr. Crane.
The spacecraft is not designed to survive the freezing temperatures of the two-week lunar night, although perhaps Odysseus will revive when the sun rises again.
“We’ll just see if our electronics make it,” Dr. Crain said. “We’ll take a look. We will hear.”
