NASA Administrator Jared Isaacman recently announced a significant restructuring of the Artemis program and how the agency intends to return astronauts to the Moon.
The new plan shortens the time between missions and redraws the map of which launches will achieve various program milestones. Nothing will change for Artemis 2which could take off in a few weeks, with four astronauts on a 10-day round trip the moon and back to Earth. However, every mission after Artemis 2 has been adjusted.
Isaacman announced the changes during a press conference on 27 February, citing unacceptable waiting times between missions for Artemis’ Space Launch System (SLS) rocket and an increased risk of relying on unproven technologies to accomplish mission-critical goals such as landing astronauts safely on the lunar surface.
Artemis 2 SLS is currently undergoing repairs in the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center in Florida, with a potential return to the launch pad in time for a launch window that opens on April 1. Artemis 2 will be the first manned flight to Orion spacecraft and the first return of astronauts to lunar space in more than half a century. Under the previous framework, it was meant to be followed by Artemis 3 in 2028, which would perform the program’s first lunar landing with astronauts aboard SpaceXs Spaceship vehicle.
For Artemis 4, NASA planned to upgrade to SLS Block 1B, which has a design powerful enough to launch elements from the Gateway space station intended for lunar orbit. Starting with Artemis 4, NASA aimed to use the Gateway outpost around the moon for deep space exploration and as an orbital stop where Orion and the program’s lunar landers could dock to transfer crews on their way down to the surface. However, Gateway is nowhere to be found in any of NASA’s recent Artemis updates.
Under NASA’s new plan, there will be no SLS Block 1B. Hoping to shorten launch cadences from the current 3.5-year interval to the desired 10 months, SLS is being standardized into a single configuration. Instead of relying on the SLS’s current upper stage for temporary cryogenic propulsion, NASA is reportedly considering convert United Launch Alliance’s Centaur V upper stage for use on the SLS for all Artemis launches after Artemis 3.
The revised The Artemis program is now targeting 2027 for the launch of Artemis 3, but instead of landing on the Moon, the mission will fly to low earth orbit for rendezvous and docking maneuvers with one or both of the Artemis program’s contracted lunar landers – SpaceX’s Starship and Blue origin‘s Blue Moon spacecraft – depending on their relative readiness for orbital missions.
NASA collaborated with SpaceX for Starship to serve as lander for Artemis 3 and 4 and contracted Blue moon for Artemis 5. But the agency is now signaling that it is ready to fly Artemis 3 with whichever lander can be made safely available when launch time rolls around.
With Artemis 3 converted to an orbiting lunar lander, Artemis 4 has been used as the program’s first crewed lunar landing, which NASA still hopes to achieve in 2028, with a possible second lunar landing that same year on Artemis 5.
It’s a major reshaping of Artemis’ original mission progression, but the plan has been intended to maximize both crew safety and NASA’s chances for success, according to Isaacman. However, the shake-up does not come without some casualties.
Gateway’s fate remains undecided under NASA’s new plan. Many components of Gateway are already inside different assembly statesbut there is now no rocket to launch them when they are ready and no mission yet assigned to meet the proposed outpost. Congress advanced one revised NASA Authorization Act on Wednesday (March 4) that supports many of Isaacman’s proposed changes to the Artemis program, but only requires him to brief lawmakers on Gateway’s status within a few months of the bill’s passage.
If Gateway is scrapped, as seems likely, there is the potential for the existing hardware to be repurposed for use in a possible base on the lunar surface, which has been a longstanding part of the Artemis program’s goals and NASA’s vision for a sustained human presence on the Moon. One of the revisions in the authorization bill even gives the NASA administrator the freedom to “repurpose, reprogram, reconfigure, or redeploy existing programs, platforms, modules, or hardware originally developed for other programs” to ensure the success of the space agency’s Artemis goals.
Canceling future SLS upgrades also has implications for some of Artemis’ ground infrastructure, which is being built to support the larger rocket variant. To transfer the 322-foot-tall (98-meter) SLS Block 1 from the VAB to the launch pad, NASA uses the massive Crawler-Transporter 2 vehicle to traverse the distance with the rocket standing on its Mobile Launch Platform (MLP). The MLP contains the SLS launch tower, which helps secure the rocket in place and provides the umbilicals that help fuel the SLS before liftoff.
Previous block upgrades to the SLS were significant enough to requires a separate MLP (Mobile Launcher 2) is built, instead of upgrading the existing platform. But in an update On March 3, NASA confirmed that “the agency no longer plans to use the Exploration Upper Stage or Mobile Launcher 2.”
The contract for Mobile Launcher 2 was awarded in 2019, and has cost about 1.6 billion dollars to date, of which approx. 98% already paid. Seven years later, Mobile Launcher 2 is currently nearing completion outside the VAB, but it may never realize its originally intended purpose. And relying on a single MLP to support Artemis launches less than a year apart could lead to a program shutdown. The SLS MLP required refurbishment from damage caused after the launch of Artemis 1 in November 2022.
Preparing the existing mobile launch vehicle for an Artemis 4 flight with a new Centaur V-based upper stage could take a year or more, because the work would go beyond normal post-launch refurbishment. Engineers must reconfigure the upper stage umbilicals, fluid and electrical interfaces, and control systems, then complete testing to certify the update for SLS launch.
Potentially losing Gateway, or having to stop construction and/or reuse the hardware from Mobile Launcher 2, is not necessarily a total loss for NASA or the Artemis program. The agency has one long history of repurposing or developing massive hardware for use on new or revised assignments. Elements from both could be used to support Artemis or other future missions as NASA’s plans continue to evolve.
