It’s increasingly unlikely that humans will fly around the Moon next year

Don't book your tickets for the launch of NASA's Artemis II mission next year just yet.

We have had reason to doubt the official September 2025 launch date for the mission, the first crewed flight into deep space in more than five decades, for a while now. This is principally because NASA is continuing to mull the implications of damage to the Orion spacecraft's heat shield from the Artemis I mission nearly two years ago.

However, it turns out that there are now other problems with holding to this date as well.

No schedule margin

A new report from the US Government Accountability Office found that NASA's Exploration Ground Systems program—this is, essentially, the office at Kennedy Space Center in Florida responsible for building ground infrastructure to support the Space Launch System rocket and Orion—is in danger of missing its schedule for Artemis II.

During this flight a crew of four astronauts, commanded by NASA's Reid Wiseman, will launch inside Orion on a 10-day mission out to the Moon and back. The spacecraft will follow a free-return trajectory, which is important, because if there is a significant problem with Orion spacecraft's propulsion system, the trajectory of the vehicle will still carry it back to Earth. At their closest approach, the crew will come within about 6,500 miles (10,400 km) of the surface of the far side of the Moon.

The new report, published Thursday, finds that the Exploration Ground Systems program had several months of schedule margin in its work toward a September 2025 launch date at the beginning of the year. But now, the program has allocated all of that margin to technical issues experienced during work on the rocket's mobile launcher and pad testing.

"Earlier in 2024, the program was reserving that time for technical issues that may arise during testing of the integrated SLS and Orion vehicle or if weather interferes with planned activities, among other things," the report states. "Officials said it is likely that issues will arise because this is the first time testing many of these systems. Given the lack of margin, if further issues arise during testing or integration, there will likely be delays to the September 2025 Artemis II launch date."

This kind of boggles the mind. Yes, the ground systems program has had to complete some important work since the Artemis I mission in late 2022, including building an emergency egress system for astronauts in the event of a problem during the launch countdown. But by September of next year, the agency will have had the better part of three years to work on those and other accommodations. At this point, there is no longer any margin in the schedule.

Heat shield in limbo

NASA also has yet to provide any additional information on the status of its review of the Orion spacecraft's heat shield. During the Artemis I mission that sent Orion beyond the Moon in late 2022, chunks of charred material cracked and chipped away from Orion's heat shield during reentry into Earth's atmosphere. Once the spacecraft landed, engineers found more than 100 locations where the stresses of reentry damaged the heat shield.

As Ars reported in September, the space agency faces a critical decision on whether to fly the heat shield as is, or make modifications.

An independent review team has completed an assessment of NASA's work on the heat shield, but NASA has not publicly commented on these results or its decision moving forward. In response to questions from Ars this week about a decision on whether to take corrective action, an agency spokesperson said, "The Artemis I heat shield investigation process is still underway, so NASA has not made any decisions yet."

To prepare for the Artemis II launch next September, Artemis officials had previously said they planned to begin stacking operations of the rocket in September of this year. But so far, this activity remains on hold pending a decision on the heat shield issue. Asked when NASA now plans to start stacking operations, the space agency official said, "We are still tracking toward stacking beginning this fall."

The bottom line is that NASA is facing schedule challenges on multiple fronts for the Artemis II mission. Although a launch delay is unlikely to be announced soon, we can be fairly confident that it is eventually coming.