Historic moon mission ends with Orion capsule splashdown | CNN

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The Artemis I mission – a 25.5-day uncrewed test flight around the moon intended to pave the way for future astronaut missions – is nearing completion as NASA’s Orion spacecraft is expected take a dip in the ocean on Sunday.

The spacecraft is completing the final leg of its journey, closing in on the thick inner layer of Earth’s atmosphere after traveling 239,000 miles (385,000 kilometers) between the Moon and Earth. It is expected to crash at 12:40 p.m. ET Sunday in the Pacific Ocean off Mexico’s Baja California. NASA will broadcast live coverage of the event, beginning at 11 a.m. ET Sunday.

The Orion capsule was supposed to splash down near San Diego, but NASA officials said Thursday that rain, wind and large waves moved there. region, and it no longer met the space agency’s meteorological criteria.

This last step will be one of the most important and dangerous steps of the mission.

“We are not out of the woods yet. The next big test is the heat shield,” NASA Administrator Bill Nelson told CNN in a Thursday phone interview, referring to the barrier designed to protect the Orion capsule from the excruciating physics of reentry. in the earth’s atmosphere.

The spacecraft will move about 32 times the speed of sound (24,850 miles per hour or nearly 40,000 kilometers per hour) when it hits the air – so fast that the compression waves will heat the vehicle’s exterior to approximately 5,000 degrees Fahrenheit (2,760 degrees Celsius). Extreme heat will also cause air molecules to ionize, creating buildup of plasma that should cause a 5 1/2 minute communications blackout, according to Artemis I Flight Director Judd Frieling.

INTERACTIVE: trace the path of Artemis that I will take around the moon and vice versa

As the capsule reaches approximately 200,000 miles (322,000 kilometers) above the Earth’s surface, it will perform a roll maneuver that briefly sends the capsule upwards – much like skipping a boulder on the surface of Earth. a lake.

There are several reasons to attempt the jump maneuver.

“The jump entry gives us a cohesive landing site that supports astronaut safety because it allows teams on the ground to coordinate recovery efforts better and faster,” said Joe Bomba, aerothermal manager at ‘Orion aerosciences at Lockheed Martin, in a press release. Lockheed is NASA’s prime contractor for the Orion spacecraft.

“By dividing the heat and force of reentry into two events, the entry jump also provides benefits such as reducing the g-forces that astronauts are subjected to,” according to Lockheed, referring to the crushing forces experienced by humans during spaceflight.

As it begins its final descent, the capsule will slow dramatically, losing thousands of miles per hour of speed until its parachutes deploy. When it splashes, Orion will be traveling 20 miles per hour (32 kilometers per hour).

Although there are no astronauts on this test mission – just a few dummies equipped to collect data and a Snoopy doll – Nelson, the NASA chief, stressed the importance of demonstrating that the capsule can make a safe return.

The space agency’s plans are to turn the Artemis lunar missions into a program that will send astronauts to Mars, a journey that will have a much faster and bolder re-entry process.

Upon return from this mission, Orion will have traveled approximately 1.3 million miles (2 million kilometers) on a path that has headed into distant lunar orbit, carrying the capsule farther than any spacecraft designed to transporting humans has never traveled.

A secondary objective of this mission was for Orion’s service module, a cylindrical attachment to the bottom of the spacecraft, to deploy 10 small satellites. But at least four of those satellites failed after being dropped into orbit, including a miniature moon lander developed in Japan and one of NASA’s own payloads that was to be one of the first small satellites to explore the Earth. interplanetary space.

During its journey, the spacecraft captured stunning images of Earth and, during two close flybys, images of the lunar surface and a fascinating “Earth elevation”.

Nelson said if he had to give the Artemis I mission a letter grade so far, it would be an A.

“Not an A-plus, simply because we expect things to go wrong. And the good news is that when they go wrong, NASA knows how to fix them,” Nelson said. But “if I am a teacher, I’d give her an A-plus.

If the Artemis I mission is successful, NASA will delve into the data collected on that flight and seek to select a crew for the Artemis II mission, which could lift off in 2024.

Artemis II will aim to send astronauts on a similar trajectory to Artemis I, flying around the moon but not landing on its surface.

The Artemis III mission, currently scheduled for launch in 2025, should to put boots back on the moon, and NASA officials said it would include the first woman and first person of color to take such a step.