NASA selected SpaceX for a $2.89 billion contract to develop a lunar lander version of its Starship vehicle and fly a demonstration mission to the surface of the moon. Credit: SpaceX

LAUREL, Md. — A SpaceX Starship that will land on the moon an on uncrewed test flight may only be a “skeleton” of the version of that will carry people on the Artemis 3 mission, NASA says.

In a presentation at the annual meeting of NASA’s Lunar Exploration Analysis Group (LEAG) here Aug. 23, Lisa Watson-Morgan, manager of the Human Landing System (HLS) program, said the Starship that performs that uncrewed landing demo mission won’t necessarily be identical to the vehicle that is used to transport astronauts to and from the surface of the moon on Artemis 3 as soon as 2025.

“For the uncrewed demo, the goal is to have a safe landing,” she said. “The uncrewed demo is not necessarily planned to be the same Starship that you see for the crewed demo. It’s going to be a skeleton because it just has to land. It does not have to take back off.”

“Clearly we want it to,” she added, referring to a takeoff, “but the requirements are for it to land.”

That uncrewed landing, scheduled for no earlier than 2024, is a key test ahead of the crewed Artemis 3 mission. Watson-Morgan said that the uncrewed landing will take place in the south polar regions of the moon, but no decisions have been made on a landing site, including whether it will be one of the 13 regions NASA announced Aug. 19 would be considered for the Artemis 3 mission. One factor in choosing a landing site, she said, was to “preserve science in the future” by not disrupting any Artemis 3 landing sites.

There will be an opportunity to do science on the uncrewed demo landing. That includes flying a suite of sensors and imagers “and potentially one payload,” she said, but didn’t specify what kinds of sensors or payloads might fly. The types of payloads NASA were interested in flying include those “that don’t require a tremendous amount of upkeep.”

However, she and others said they want to maximize the performance that Starship offers on lunar landings, with the potential to carry large payloads. While the original HLS competition had a requirement to carry only 100 kilograms of cargo to the surface and back in addition to two astronauts, said Logan Kennedy, HLS surface lead at NASA, the later “sustained” missions will increase that to 182 kilograms to the surface and 160 kilograms back, with a goal of 1,000 kilograms down and back.

“We’re going to leverage all that we can on this mission to try and take up and down as much as we can, using the size of their system,” Watson-Morgan said.

She said SpaceX has been a “fantastic partner” on HLS so far, with close cooperation between the company and the agency. SpaceX has been involved in the Artemis 3 landing site selection process to ensure potential landing regions are compatible with Starship. NASA, in turn, has its personnel, including astronauts, visiting SpaceX facilities for reviews and hardware tests.

That includes one of the unique attributes of Starship, the elevator required to go from the crew cabin to the surface. “It’s a very tall lander. It doesn’t look like the traditional landers that we’ve all seen in the past, so it can be hard to reconcile that mentally,” Watson-Morgan said.

She assured scientists at the meeting that the elevator design was robust, saying it was “multi-fault-tolerant” and designed for operating in lunar conditions. In his presentation, Kennedy showed images of a full-scale mockup of the elevator that SpaceX built for “crew-in-the-loop” tests, including ones where astronauts wore simulated spacesuits to test the ability to get in and out of the elevator.

Some aspects of the overall Starship lunar landing architecture, though, remain unclear. The concept of operations for the lander involves SpaceX launching a Starship into low Earth orbit that will serve as a fuel depot, which is filled by subsequent Starship launches that serve as tankers. The lunar lander Starship will then launch, fill its tanks at the depot, and head to lunar orbit.

Neither NASA nor SpaceX, though, have said exactly how many launches will be required for a single Starship lunar landing mission, an issue of contention during protests of the SpaceX HLS award last year by Blue Origin. “How many? However many is needed. That is how many we’ll launch,” Watson-Morgan said.

NASA’s requirements for HLS missions end once the astronauts are returned to Orion. “We don’t tell them to do anything with it,” Kennedy said of the fate of the Starship lander after returning astronauts from the lunar surface. “That’s going to be up to SpaceX.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...