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Intuitive Machines’ unmanned Odysseus moon landing almost failed due to a single safety switch.
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Other moon landing attempts have crashed or burned due to leaking valves or software problems.
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Their photos show how even the smallest details make a huge difference in space travel.
Landing on the moon is so difficult that until last year, only three countries had ever done it without crashing. Recently, India, Japan and a private company – Intuitive Machines – have joined them.
Thursday’s Intuitive Machines moon landing was particularly significant, returning the U.S. to the moon’s surface for the first time in nearly 52 years and gently landing the first commercial spacecraft on the moon.
But the mission narrowly avoided the same fate as several moon landing attempts before it: death from a minor technical error.
The Houston-based company’s unmanned Odysseus lander was almost lost due to one of the smallest possible mistakes. A safety switch that should have been turned off before launch was instead left on, effectively disabling the navigation system that was supposed to guide the robot to a safe landing site.
With less than two hours to go before landing, Intuitive Machines engineers frantically put together a new navigation system. They reprogrammed the spacecraft to instead use the laser technology from a NASA experiment that took it to the moon. The experiment was not intended to land the spacecraft, but it worked in a pinch.
But at the last moment the lander tipped over and ended up on its side. This does not seem to be related to the incorrect safety switch.
“Space travel is hard. You have to have a million things go right, and if one thing goes wrong, you can still have a failure,” Trent Martin, vice president of space systems at Intuitive Machines, said during a NASA press conference in January, to soften. before Odysseus was launched.
Several robotic moon landing attempts have failed or otherwise failed in recent years. Overall, only about 50% of moon landing missions are successful.
In every recent case, failure comes down to small technical details: a million steps, only one of which goes wrong. Photos from those missions show how important the little things are in space travel.
Astrobotic’s lander may have succumbed to a leaking valve
Sometimes all it takes to kill a moon landing is just a small piece of inadequate hardware.
Just a month before Intuitive Machines triumphed, Astrobotic – another American company that partnered with NASA to reach the moon – failed.
Just hours after launch, Astrobotic’s Peregrine lander began leaking fuel. When he sent his first photo to Earth, it showed the lander’s insulation was crumbling.
Astrobotic said the most likely cause was a valve in the fuel tank system that failed to reseal. That small failure was enough to deplete the lander of fuel, cause the crumple in the photo, and ultimately wipe out the mission.
Landing on the moon had become impossible, Astrobotic decided, so Peregrine burned up in Earth’s atmosphere.
3 Moon Crashes Show How Time Is Compressed in the Final ’15 Minutes of Terror’
Especially in the final phase of the descent, there is virtually no room for error during a moon landing.
India learned this from its first attempt to land on the moon in 2019. The Vikram lander crashed on the moon because it braked faster than the braking system was programmed for, SpaceNews later reported.
NASA’s Lunar Reconnaissance Orbiter (LRO) later discovered Vikram’s remains scattered across the moon’s surface.
In those final phases, a spacecraft is completely self-contained. There is no time for mission operators to respond to new data from the spacecraft, write new commands and send them back to the moon.
“Time is being compressed tremendously,” Robert Braun, head of space exploration at the Johns Hopkins Applied Physics Laboratory, previously told Business Insider. “There is very little margin to try something again if it doesn’t happen as planned.”
That is why Kailasavadivoo Sivan, then director of India’s space program, has called this final phase ’15 minutes of terror’.
Last year, the Japanese company ispace also lost its lunar lander in those final stages, just a few kilometers above the moon’s surface, due to a software problem. LRO also saw that lander in pieces:
“Once you start a landing sequence, you’re committed. It’s like jumping out of a plane,” Braun said. “Your parachute has to work.”
The Beresheet lander, from Israeli nonprofit SpaceIL, also went into freefall during the critical final stages of its landing in 2019. A single computer command led to a series of technical problems that caused the main engine to fail. LRO also saw the wreck:
Japan’s reverse moon landing survived a major failure
Japanese Smart Lander for Exploring the Moon (SLIM) recently survived a major outage – with a twist.
One of the lander’s two main engines failed during descent, causing the spacecraft to tumble. It survived the chaotic fall and managed to deploy the two small robbers it was carrying.
But a photo from one of those rovers later revealed that the lander had landed upside down.
That left the solar panels pointed away from the sun, which took a toll on the spacecraft’s power generation and left the spacecraft with too little battery power to carry out much of its mission.
The case of SLIM shows that extremely robust hardware and software engineering, plus a healthy dose of luck, can help a lander do its job despite a few mistakes.
Likewise, Intuitive Machines’ success on Thursday shows that small mistakes don’t necessarily mean the end of a mission.
“Space is difficult and equipment doesn’t always work as expected,” Braun told Business Insider after Odysseus landed. “In this case, engineers on the ground came up with an ingenious way to keep the mission on track and actually complete the landing.”
Read the original article on Business Insider