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The Artemis I mission, a 25½-day unmanned test flight around the moon meant to pave the way for future astronaut missions, is drawing to a close as NASA’s Orion spacecraft is expected. to make a splashdown in the ocean on Sunday.
The spacecraft is completing the final leg of its journey, approaching the thick inner layer of Earth’s atmosphere after traversing 239,000 miles (385,000 kilometers) between the Moon and Earth. It is scheduled to splash down at 12:40 pm ET Sunday in the Pacific Ocean off Mexico’s Baja California. NASA will go on the air live coverage of the event, beginning at 11 am ET on Sunday.
The Orion capsule was scheduled to splash down near San Diego, but NASA officials said Thursday that rain, wind and large waves had moved there. area, and no longer met the space agency’s meteorological criteria.
This final step will be one of the most important and dangerous stages 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 phone interview Thursday, referring to the barrier designed to protect the Orion capsule from the unbearable physics of re-entering the Earth. terrestrial atmosphere.
The spacecraft will be traveling at 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 cause the exterior of the vehicle to heat up to about 5,000 degrees. Fahrenheit ( 2,760 degrees Celsius). Extreme heat will also cause air molecules to ionize, creating a buildup plasma that is expected to cause a five and a half minute communications blackout, according to to Artemis I flight director Judd Frieling.
INTERACTIVE: Trace the path Artemis will take around the moon and back
As the capsule reaches around 200,000 feet (61,000 meters) above the Earth’s surface, it will perform a roll maneuver that briefly sends the capsule upward, much like skipping a rock across the surface of a lake.
There are a couple of reasons to try the jump maneuver.
“Jumping the gate gives us a consistent landing site that supports astronaut safety by allowing teams on the ground to better and faster coordinate recovery efforts,” said Joe Bomba, Lockheed Martin aerosciences aerothermal lead at Orion, it’s a statement. statement. Lockheed is NASA’s prime contractor for the Orion spacecraft.
“By dividing the heat and force of re-entry into two events, jump-in also offers benefits such as lessening the forces that astronauts are subjected to,” according to Lockheed, referring to the crushing forces humans experience during astronauts. space flights.
As it embarks on its final descent, the capsule will dramatically slow down, losing thousands of miles per hour until its parachutes deploy. By the time it falls, Orion will be traveling at 20 miles per hour (32 kilometers per hour).
While there are no astronauts on this test mission, only one some mannequins equipped to collect data and a snoopy doll — Nelson, the head of NASA, has stressed The importance to prove that the capsule can make a safe comeback.
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 returning from this mission, Orion will have traveled approximately 1.3 million miles (2 million kilometers) on a looping path toward a distant lunar orbit, carrying the capsule. farther than any spacecraft designed to transport humans have ever traveled
A secondary goal of this mission was for the Orion Service Module, a cylindrical accessory at the bottom of the spacecraft, to deploy 10 small satellites. But at least four of those satellites have failed after being launched into orbit, including a miniature lunar lander developed in Japan and one of NASA own payloads that it was destined to be one of the first tiny satellites to explore interplanetary space.
On its journey, the spacecraft captured awesome photos of Earth and, during two close flybys, images of the lunar surface and a fascinating “earth rise.”
Nelson said that 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 schoolteacher, I’d give her an A-plus.”
If the Artemis I mission is successful, NASA will dive into the data collected on this flight and look to pick a crew for the Artemis II mission, which could take 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 a 2025 releaseexpected to put the boots back on the moon, and NASA officials have said it will include the first woman and first person of color to achieve such a milestone.
