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The Artemis I mission — a 25½-day uncrewed test flight around the Moon designed to pave the way for future astronaut missions — is coming to an end in anticipation of NASA’s Orion spacecraft. to make an ocean splash on Sunday.
After traveling 239,000 miles (385,000 kilometers) between the Moon and Earth, the spacecraft is nearing the thick inner layer of Earth’s atmosphere, completing the final leg of its journey. It is set to make a splash in the Pacific Ocean off the coast of Baja California, Mexico at 12:40 a.m. ET on Sunday. NASA will broadcast Live broadcast The event starts at 11:00 a.m. on Sunday.
The Orion capsule was scheduled to splash down near San Diego, but NASA officials said Thursday that rain, wind and large waves were driving it there. area and it no longer met the space agency’s weather criteria.
This last step will be one of the most important and dangerous legs 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 excruciating physics of re-entry into Earth’s atmosphere.
As the spacecraft hits the air, it will travel at about 32 times the speed of sound (24,850 miles per hour, or about 40,000 kilometers per hour)—so fast that compression waves will cause the exterior of the vehicle to heat up to about 5,000 degrees Fahrenheit (2,760 degrees Celsius). Excessive heat will also cause the air molecules to ionize, causing condensation plasma expected to cause 5½ minutes of communication interruption, according to To Judd Frieling, Artemis I flight director.
INTERACTIVE: Follow Artemis’s path around the moon and back
When the capsule reaches an altitude of about 200,000 miles (322,000 kilometers) above Earth’s surface, it will perform a roll maneuver that will briefly send the capsule back up—kind of like skipping a rock on the surface of a lake.
There are several reasons for attempting a jump maneuver.
“Skip Access gives us a consistent landing area that supports astronaut safety because it allows teams on the ground to coordinate recovery efforts better and faster,” said Joe Bomba, Lockheed Martin’s Orion aerothermal head. statement. Lockheed is NASA’s prime contractor for the Orion spacecraft.
According to Lockheed, referring to the crushing forces experienced by humans during spaceflight, “By splitting the heat and re-entry force into two events, reentry also offers the benefit of reducing the G-forces experienced by astronauts.”
As it makes its final descent, the capsule will slow down dramatically and travel at thousands of miles per hour until its parachutes open. Orion will be traveling 20 miles per hour (32 kilometers per hour) when it hits the ground.
While there were no astronauts on this test mission – just a several mannequins equipped to collect information and To the Snoopy doll – NASA chief Nelson emphasized importance to demonstrate that the capsule can be returned safely.
The space agency’s plans are to turn Artemis’ moon missions into a program that would send astronauts to Mars, a journey that would be a faster and more daring re-entry process.

After returning from this mission, Orion will have traveled approximately 1.3 million miles (2 million kilometers) on its way to distant lunar orbit carrying the capsule. farther than any spacecraft designed to carry humans have you ever traveled
The second objective of this mission was to place 10 small satellites on Orion’s service module, a cylindrical appendage under the spacecraft. But at least four of these satellites failed after launch, including a miniature lunar lander. Japan and one NASA’s own payloads It was intended to be one of the first small satellites to explore interplanetary space.
During the journey, the spacecraft was intercepted amazing pictures Images of Earth and the surface of the Moon during two close flybys and the fascinating “The earth rises.”
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. The good news is that when they go wrong, NASA knows how to fix them,” Nelson said. But “if I a teacher, I’d give it an A-plus.”
If the Artemis I mission is successful, NASA will dive into the data collected on that flight and try to select a crew for the Artemis II mission, which could lift off in 2024.
Artemis II will aim to send astronauts flying around the Moon on the same trajectory as Artemis I, but not landing on its surface.
Artemis III mission, right now It is planned to be released in 2025is expected Putting the boots back on the moon will include the first woman and the first person of color to reach such a milestone, NASA officials said.