The landing is scheduled off the Mexican island of Guadalupe at 6:39 p.m. HB (9:39 a.m. local time).
The success of this mission, which will have lasted just over 25 days in total, is crucial for NASA, which has invested tens of billions of dollars in the American program to return to the Moon, Artemis, whose goal is to prepare for a future trip to Mars.
A brand new astronaut-less vehicle
The first test flight of this brand new vehicle – without an astronaut on board this time – has so far been a real success.
But it is only during the last minutes of the mission that its main objective must be accomplished: testing the capsule’s heat shield, the largest ever built (5m in diameter).
“It’s a critical piece of safety, designed to protect the spacecraft and its passengers,” explained Mike Sarafin, mission manager. “The heat shield has to work.”
In 2014, a first test of the capsule had been carried out, but it had not then left Earth orbit, and had therefore entered the atmosphere more slowly (about 32,000 km / h).
A whole recovery system put in place
A US Navy ship, the USS Portland, has been pre-positioned for capsule recovery operations, which NASA has been training for years. Helicopters and inflatable boats will also be deployed.
The spacecraft will first be slowed down by the Earth’s atmosphere, then by a series of no less than eleven parachutes, until it reaches a speed of around 30 km/h when it hits the water.
Once landed, it will be left in the water for two hours, much longer than if astronauts were on board, in order to collect data.
“We will see how the heat is absorbed by the capsule and how this affects the temperature inside”, detailed Jim Geffre, responsible for Orion at NASA.
Then divers will attach cables to it in order to tow it to the interior of the ship, the rear of which will be partly submerged. The water will then be pumped, allowing the capsule to be slowly deposited on a support provided for this purpose.
Operations are expected to take between four and six hours
The ship will then take the road to San Diego, on the American west coast, where the capsule will be disembarked a few days later.
In total, the spacecraft will have traveled more than 2.2 million kilometers in space since its takeoff on November 16 during the first flight of NASA’s new mega-rocket, SLS.
Orion flew by the Moon only some 130 kilometers from its surface, and ventured up to more than 430,000 km from our planet.