Quick thinking and a stroke of luck averted Moon lander disaster thanks to Intuitive Machines


Intuitive Machines' spacecraft landed on the lunar surface yesterday. , , On the side. CEO Steve Altemus confirmed during a press conference on Friday that, although it was not a perfect landing, it was nothing short of a miracle that the spacecraft landed intact.

Using a small model of the lander, Altemus showed how engineers believe the spacecraft, called Odysseus, touched down given the most recent telemetry data.

“The vehicle is stable at or near our intended landing site,” Altemus said. “We're downloading data from buffers in the spacecraft and commanding the spacecraft.”

Intuitive Machines confirmed yesterday that the lander touched down on the surface at 5:24 p.m. Central time – making the company the first company to land a privately built spacecraft on the Moon – but many details about the health of the vehicle were unknown. One reason for this is that the onboard camera, a device called EagleCam, was turned off during landing. Without images, engineers had to rely on other data to determine the lander's direction after landing.

Even now, the company continues to reconstruct the chain of events leading up to the historic landing. The company originally thought of Odysseus was really straight, but Altemus said it was based on “stale” telemetry data. Currently available information is indicating that the spacecraft was indeed vertical at the time of touchdown, but because it was also moving horizontally – and a little too quickly – it is likely that one of its legs got caught on something. Or broke, causing it to bend.

The good news is that most of the onboard payload is not on the bottom-facing panel – the only panel that is not needed to operate on the lunar surface. The company was able to confirm that several key subsystems – including the solar arrays that provide power to the spacecraft and onboard payloads – are performing well.

Much of the mission's success was due to the very quick thinking of Intuitive Machines' mission controllers – and that's a stroke of very good luck.

Intuitive Machines CEO Steve Altemus during a press conference after the IM-1 landing

Intuitive Machines CEO Steve Altemus during a press conference after the IM-1 landing. Image Credit: NASA

The navigational problems began after Odysseus conducted a planned maneuver called lunar orbital insertion on Wednesday night, which placed it in an elliptical orbit around the moon. This proved extremely “accidental”, Altemus said, as it caused mission controllers to attempt to use a navigational subsystem called a “laser rangefinder” much earlier than planned (the lasers were going to be activated for the first time during the final descent phase). ).

After reviewing the data, the company realized on the morning of landing that the lasers were not working – because they had not turned off the physical safety switch on the component while it was still on the ground.

These lasers determine variables important to landing, such as altitude and horizontal velocity; Upon their deactivation, Odysseus could suffer the fate of many other landers and crash on the surface. The company considered a handful of options, but ultimately they decided to use the NASA Doppler Lidar payload as a technology demonstration. He instructed Odysseus to orbit the Moon for an additional two-hour period, to give them more time to load software patches and reset the lander's guidance, navigation, and control systems.

It was a remarkable save in the last minute. Prasun Desai, deputy associate administrator for NASA's Space Technology Mission Directorate, said during the press conference that the agency had hoped to bring Doppler lidar technology to a technology readiness level (TRL) of 6, but the successful execution on Odysseus has brought it . Up to TRL 9, the highest level of readiness.

“All that hard work paid off yesterday when a technical problem occurred and the teams decided it was best to try to switch and rely on this technical performance,” he said. “What we understand from the telemetry received, which is limited up to this point until we get all the data back, is that the technology has performed flawlessly.”