NASA’s Return to the Moon: Well, There’s Good News and Bad News

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NASA has finally provided much-anticipated updates on its Artemis lunar program, addressing concerns about the Orion spacecraft and mission timelines. The news isn’t as a bad as we feared, but we’re going to have to wait a bit longer for America’s return to the Moon.

NASA has found a way around the Orion capsule’s heat shield issue, but the space agency’s return to the lunar surface is facing more delays due in part to safety concerns with the crew spacecraft.

During a media briefing on Thursday, NASA announced that its Artemis 2 and 3 missions have been delayed, with the first crewed flight of Orion slipping from September 2025 to April 2026, and the first Moon landing since Apollo now scheduled for sometime in mid-2027 instead of 2026.

“We need to get this Artemis 2 test flight right to ensure the success of our return to the Moon…in order for the rest of the Artemis campaign to proceed,” NASA Administrator Bill Nelson told reporters. “Space is demanding, and we…need this time to make sure that the Orion capsule can safely deliver our astronauts to deep space and back to Earth.”

NASA has been working to resolve an issue related to Orion’s heat shield, which came up during the Artemis 1 mission in 2022. Artemis 1 was an uncrewed test flight of the Orion spacecraft to the Moon and back. After the Artemis 1 mission splashed down in the Pacific Ocean, follow-up inspections of the capsule revealed an unexpected performance from its heat shield. During Orion’s reentry through Earth’s atmosphere, the spacecraft traveled at speeds reaching 24,600 miles per hour (39,590 kilometers per hour) and its heat shield endured temperatures above 5,000 degrees Fahrenheit. Although NASA engineers had anticipated that some charring would occur, more of the shield’s ablative material came off than they had expected.

Earlier in May, the NASA Office of Inspector General released a report to address NASA’s readiness to launch its Artemis 2 mission, identifying Orion’s heat shield as one of the critical issues that need to be addressed before the trip to the Moon and back.

For its return to Earth, Orion performed what is referred to as a “skip entry,” according to NASA deputy administrator Pam Melroy. “This is a technique we use coming back from the Moon because the velocity of the spacecraft and the energy that it has to dissipate is much greater than the energy that you dissipate just coming back from low Earth orbit,” Melroy told reporters. “So the way it’s designed is to dip in and out of the atmosphere to reduce the velocity.”

While it was dipping in and out of the atmosphere, heat accumulated inside the heat shield’s outer layer, which led to gasses forming and becoming trapped inside the heat shield. This led to a buildup of internal pressure, which then led to the cracking and uneven shedding of the heat shield’s outer layer, according to Melroy. “We had to understand why that erosion variation in the heat shield occurred to make sure that our astronauts would be safe during Artemis 2,” she added.

After identifying the root cause, NASA opted to keep Orion’s heat shield as is for Artemis 2, while applying a modified entry trajectory for the spacecraft returning to Earth.

Even with that solution, the space agency must still prioritize astronaut safety before launching a crew aboard Orion. This, however, does mark another disappointing delay to the Artemis program, which has suffered from cost overruns and an overly ambitious timeline. The Artemis 2 mission was originally scheduled for November 2024 and the follow-up Artemis 3 mission was originally scheduled for late 2025. With the latest development, the follow-up Artemis 2 mission will launch nearly five years after the initiation of the lunar landing program.

NASA is facing pressure to land astronauts on the Moon before China gets there first, with the two nations racing with one another in a newly formed space race. NASA administrator Nelson, however, reassured that, even with the new timeline, the U.S. is still ahead of China. The Chinese space program announced plans to land astronauts on the Moon in 2030, so that gives NASA a three year head start, for now at least.

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