Artemis 2 crew members Jeremy Hansen (from left), Victor Glover, Reid Wiseman and Christina Koch will have to wait a few more months before flying around the moon and back. Credit: James Blair/NASA
For the second time this year, NASA has pushed back its timeline for landing the first Americans on the Moon since the Apollo era.
NASA Administrator Bill Nelson on Thursday revealed that due to a problem with the heat shield of NASA’s Orion capsule discovered during the 2022 Artemis 1 test mission, the lunar landing of Artemis 3 – originally scheduled for 2025 and a January postponed to September 2026 – will now take place no earlier than mid-2027.
NASA also pushed Artemis 2 — a 10-day crewed trip around the Moon and back — from September 2025 to no earlier than April 2026. The delays are not entirely unexpected, in line with a 2023 assessment from the Government Accountability Office of the United States that Artemis’s timelines were “unlikely” to meet.
Nelson, speaking at a news conference at NASA Headquarters in Washington, D.C., was joined by NASA Deputy Administrator Pam Melroy, Associate Administrator Jim Free and Amit Kshatriya, Deputy Associate Administrator for NASA’s Moon to Mars Program space agency, as well as for Artemis 2. mission commander Reid Wiseman.
“We have to get [Artemis 2] just to ensure the success of our return to the Moon, and then return here safely to Earth, so that the rest of the Artemis campaign can proceed,” Nelson told reporters.
Diagnosis of the problem
According to officials, the delays of Artemis 2 and Artemis 3 can be traced to an anomaly that engineers discovered during Artemis 1 but hadn’t fully understood until now.
When re-entering Earth’s atmosphere after returning from the Moon, Orion can reach speeds 32 times faster than the speed of sound. To slow it down, NASA on Artemis 1 performed something called skip reentry: the capsule briefly “dips” into the atmosphere before “skipping” back into space, like a rock skipping through water. This deceleration allows NASA to spot Orion landing near the coast, making it easier for the spacecraft’s crew to recover.
Artemis 1 was NASA’s first failed reentry attempt with a human spacecraft. But the maneuver did not go according to plan.
Orion’s heat shield is covered in an outer layer of material called Avcoat, designed to protect the capsule and its crew from temperatures approaching 15,000 degrees Fahrenheit during reentry. Avcoat is designed to wear off as it heats up. But an internal NASA investigation found that the heat shield trapped gases that created cracks in the material, causing charred pieces to escape.
This was not predicted by NASA’s ground tests, which were conducted at a higher temperature than Orion actually experienced. As a result, the models predicted that the heat shield would be fine.
According to flight data from Artemis 1, if Orion had had a crew, the capsule would have remained cool enough for the astronauts to be comfortable during reentry. But NASA didn’t fully understand why the charred pieces flew off the spacecraft, requiring further analysis.
What’s the next step?
NASA engineers were able to recreate the temperatures Orion actually experienced inside the bow jet facilities at the space agency’s Ames Research Center in California. After testing, an executive board unanimously decided that a new Orion heat shield would not be necessary for Artemis 2.
Staff began stacking parts of NASA’s Space Launch System (SLS) rocket for Artemis 2 in November. But SLS has a limited “life” after which its propellant will degrade. Instead of modifying the heat shield for that mission — which Nelson on Tuesday said would push Artemis 3 even farther, to the end of 2028 — NASA is confident it can shorten each “jump” during reentry by limiting gas buildup that happened in the previous mission.
A new heat shield will instead be incorporated on Artemis 3. Kshatriya, supporting the move, said the agency’s investigation produced “one of the most magnificent pieces of engineering analysis I have ever been a part of.”
NASA said Thursday that the additional time before Artemis 2 will also allow engineers to make necessary upgrades to Orion’s life support systems, which Nelson said “need to be checked.” Kshatriya said it was “taking longer than we thought” to address the problem.
He added that NASA contractor Axiom Space, which together with Prada is designing the next-generation spacesuits that Artemis astronauts will wear on the Moon, is “struggling” to develop its own life support system. Nelson called on business partners to “redouble efforts to meet and improve this agenda.”
The NASA administrator was adamant that the United States would return Americans to the Moon “well ahead of the Chinese government’s announced intent” to do so in 2030, assuming SpaceX’s Starship lunar lander is ready in time. Nelson said Gwynne Shotwell, SpaceX president and chief operating officer, is “next [his] list to call” on the updated timing of the mission. Next year, NASA wants to see SpaceX perform an orbital transfer of propellant between two spaceships. But Kshatriya said “there will be risks to that delivery.”
Nelson said he has already spoken to the CEOs of other Artemis contractors such as Blue Origin, Boeing, Lockheed Martin and Axiom, as well as Jared Isaacman, chosen by US President-elect Donald Trump to succeed him. Isaacman, CEO of Shift4 Payments and an astronaut himself, maintains close ties to SpaceX through its Polaris program.
“The safety of our astronauts is always at the forefront of our decisions,” Nelson said. “It is our north star. We don’t fly until we’re ready. We don’t fly until we know we have made the flight as safe as possible for the humans on board.”
However, if Nelson’s words are any indication, the space agency is in a time crunch. He called the lunar south pole, where Artemis 3 will land, “vital” to U.S. interests and warned that the area – which hosts water ice within its permanently shadowed craters – cannot be “surrendered to the Chinese.”
