[Reading Science] The Moon Goddess Returning at 13 Times the Speed of a Bullet

Artemis 1 Orion Spacecraft to Return on the 11th Afternoon (US Eastern Time)
Key Question: Can the Heat Shield Protect the Hull and Passengers?

The National Aeronautics and Space Administration (NASA) is conducting a rehearsal for the recovery of the Orion spacecraft. Photo by NASA

[Asia Economy Reporter Kim Bong-su] The "Goddess of the Moon" is returning to Earth at a speed 13 times faster than a bullet. Can it withstand the tremendous frictional heat and shock waves of the atmosphere and safely return?

The U.S. National Aeronautics and Space Administration (NASA) announced on the 10th that the Orion spacecraft of Artemis 1 (Goddess of the Moon), which was test-launched to resume manned lunar exploration after more than 50 years, is scheduled to land off the coast of Isla Guadalupe, west of Baja California, Mexico, at 12:40 PM (Eastern Time) on the 11th.

NASA initially planned to land near the coast of San Diego, California, but moved the landing site 550 km south due to expected bad weather. According to space news outlet SpaceNews, Mike Sarafin, NASA's Artemis 1 manager, explained, "Due to wind, waves, and some rain, recovery operations were expected to be difficult, so we relocated the landing area."

The landing and recovery of the Orion spacecraft are expected to proceed without issues. The U.S. Navy ship USS Portland will arrive at the expected location at least 24 hours before landing to collect weather information and prepare for recovery. The Orion spacecraft will remain on the water surface for two hours after landing to check the condition of the hull, then will be towed by helicopters and small boats onto the USS Portland.

NASA's Orion spacecraft development team is on edge about whether it can land safely. The Orion spacecraft, which will orbit the Moon for about three weeks before returning, will enter Earth's atmosphere at a speed of 40,000 km/h. It must endure tremendous shock and frictional heat with the atmosphere. Especially since no facility on Earth has been able to simulate such speed, weight, impact, and heat conditions for testing, success cannot be easily guaranteed. Manager Sarafin said, "(The Orion spacecraft, which will carry lunar astronauts) is critical for safety," adding, "The heat shield must function as designed to protect the spacecraft itself, passengers, and pilots."

The "Skip Reentry" method that the Orion spacecraft will use to protect the hull and occupants is also attracting attention. This method involves descending to an altitude of 60 km, then ascending again to 90 km to minimize shock waves on the spacecraft and occupants caused by collision with the surface, and to broaden the range of possible final landing sites. Safely recovering the Orion spacecraft is also an important task.

NASA plans to review the technologies applied during this Orion spacecraft's reentry, landing, and recovery process and improve and utilize them for the Artemis 2 mission, a manned lunar orbit round-trip project scheduled after 2024.

NASA has completed more than 30% of the 124 scientific experiments planned to be conducted via the Orion spacecraft, with 37.5% ongoing through data collection during navigation. The remaining 32.5% will mainly be conducted after flight, monitoring seawater exposure and corrosion of the spacecraft hull during reentry, descent, and recovery.

Through the Artemis 1 launch, NASA developed, tested, and succeeded with the Space Launch System (SLS), the most powerful heavy-lift launch vehicle in human history. It can carry 143 tons to low Earth orbit and up to 27 tons for lunar orbit insertion. The Orion spacecraft carried three mannequins dressed in actual spacesuits intended for lunar exploration to study the effects of space radiation and prepare for situations astronauts may face during future manned missions. It also tested an automatic navigation system equipped with large screens and voice guidance devices to enable astronauts to control the spacecraft easily and quickly.

NASA also plans to focus research on identifying and improving the cause of 17 current regulator errors that occurred during the Orion spacecraft's navigation period.