After the brilliant success of the Artemis I mission, why are there two years left for an encore?

The launch of the Artemis I mission in mid-November was spectacular, and NASA’s Orion spacecraft has performed almost flawlessly ever since. If all goes as expected, and there’s no reason to believe it won’t, Orion will splash into calm seas off the coast of California this weekend.

This exploratory mission has provided dazzling photos of Earth and the Moon and offered the promise that humans will soon fly into deep space again. So the question for NASA is when can we expect an encore?

Realistically, a follow-up to Artemis I is probably at least two years away. The Artemis II mission most likely won’t happen before early 2025, though NASA isn’t giving up hope of launching humans into deep space by 2024.

It may seem strange that there is such a long gap. After all, with its flight in November, the Space Launch System rocket has now demonstrated its capability. And if Orion returns to Earth safely, it will validate the calculations of the engineers who designed and built its heat shield. Should it really take more than two years to finish building a second rocket and spacecraft and complete certification of the life support systems inside Orion?

The short answer is no, and the reason for the long gap is somewhat absurd. It all goes back to a decision made about eight years ago to plug a $100 million budget hole in the Orion program. As a result of a chain of events that followed this decision, Artemis II is unlikely to fly before 2025 due to eight relatively small flight computers.

“I hate to say it’s Orion that’s holding us back this time,” Mark Kirasich, who served as NASA’s program manager for Orion when the decision was made, said in an interview. “But I’m bringing up the rear. And it’s part of my legacy.”

A long time ago, in a distant budget

About eight years ago, senior NASA officials and Orion’s prime contractor, Lockheed Martin, needed to fill a budget gap. At the time, NASA was spending $1.2 billion a year to develop the Orion spacecraft, and while the design was moving forward, there were still challenges.

NASA’s exploration plans at the time were substantially different from today’s Artemis program. Nominally, the agency was building Orion and the SLS rocket as part of a “Journey to Mars.” But there was no clear plan on how to get there and no well-defined missions for Orion to fly.

A key difference is that NASA only planned to fly the original version of the SLS rocket, known as “Block 1,” once. After this initial mission, the agency planned to improve the rocket’s upper stage, making a version of the rocket known as “Block 1B”. Because this variant was taller and more powerful than the Block 1, it required major modifications to the rocket launch tower. NASA engineers estimated that it would take nearly three years of work after the initial SLS launch to complete and test the rebuilt tower.

So it seemed plausible that Orion’s planners could reuse some components from their spacecraft’s first flight on the second. In particular, they focused on a set of two dozen avionics “boxes” that are part of the electronic system that operates Orion’s communications, navigation, display and flight control systems. They estimated it would take about two years to re-certify the flight hardware.

By not having to build two dozen avionics boxes for Orion’s second flight, the program closed a $100 million budget hole. And schedule-wise, they would have almost a year to spare while the launch tower was being worked on.

“It was simply a budget decision,” Kirasich said. “The release dates were completely different at the time.”