American probe on the Moon | The ups and downs of a lunar lander

Even though the lander landed on the Moon horizontally rather than upright, which severely limited its scientific activities, the private Odysseus mission was declared a success Wednesday at a press conference. The firm Intuitive Machines described the 11 “challenges” that complicated the mission.

Odysseus should stop transmitting data by Thursday morning, due to night falling on the lunar South Pole. “We will know in two or three weeks if it is possible to revive her,” said Intuitive Machines CEO Steve Altemus during the press conference organized by NASA, which is funding the mission. “We are not sure because the batteries are not designed to withstand such prolonged cold. Neither does the on-board computer. »

This week, the Japanese lander SLIM started sending data again after a month of hibernation during a similar lunar night. SLIM also landed horizontally, in January, but closer to the equator. Odysseus set a record for landing near the lunar South Pole.

The hazards of the Odysseus mission, which took off from Florida on February 15 and landed on the moon on the 22, are numerous. The most serious was an oversight: a laser range finder, which was supposed to give the precise distance to the lunar surface during the final approach, could not be used because a safety catch had not been deactivated before the launch .

Fortunately, this oversight was detected before the moon landing. “We had a somewhat elliptical orbit, so we decided to use the rangefinder to check our altitude,” Mr. Altemus said. That’s when we realized the situation. Tim Crain [le directeur technologique de la firme] turned pale when I told him we were going to land without a rangefinder. »

It was ultimately Mr. Crain who found the solution: using an experimental NASA device, which was to be tested during the mission, to assist the moon landing. “Normally, it takes a month to integrate a new instrument into a critical element of the mission. We did that in an hour,” Mr. Altemus said.

But the moon landing was partly compromised by this haste. Odysseus found himself lying down. Its solar panels did not capture enough light to power the batteries for the expected duration of the mission, ten days. And its main antenna pointing towards the surface of the Moon. Signals bounced around before reaching Earth, decreasing the amount of information that could be transmitted.

If the laser range finder had been functional, the moon landing would have been flawless, according to Mr. Altemus.

All the scientific instruments were nevertheless able to be tested. “The reduced duration of the mission is not ideal, but the mission was an unprecedented success,” he told The Press Christian Sallaberger, CEO of Canadensys, an Ontario firm that supplied seven cameras to Odysseus.