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White House budget seeks to end SLS, Orion, and Lunar Gateway programs

“SLS alone costs $4 billion per launch and is 140 percent over budget.”

Eric Berger – May 2, 2025 11:39 am | 162

NASA's SLS rocket is seen at sunrise on June 7, 2022, after its second trip to the launch site. Credit: Trevor Mahlmann

The White House released a “skinny” version of its budget proposal for fiscal year 2026 on Friday, including financial information for all federal agencies. A “skinny” budget simply means that while the document contains top-line numbers for agencies and their programs, it does not provide much in the way of specific allocations.

The document was delivered to the Senate Committee on Appropriations on Friday and signed by Russell Vought, director of the White House Office of Management and Budget. A “full fiscal plan” will follow in the coming weeks. This is the first step in the budget process, in which Congress has the critical role of actually writing a budget.

“I look forward to working with you to achieve significant budgetary savings for the American people within the spending programs under your jurisdiction,” Vought wrote.

About NASA

The budget contains some notable changes for the US space agency. Overall, NASA is asked to take a 25 percent cut in its budget, from about $25 billion to $18.8 billion.

Ars has previously reported on some of these proposed cuts, most notably to its science budget. These include a $2.265 billion reduction in Space science and a $1.161 billion reduction in Earth science. Perhaps the most notable cancellation here is the Mars Sample Return mission, which the budget proposal says will be achieved by human missions to Mars.

There are also significant changes proposed in NASA’s biggest-ticket exploration programs. The budget would cancel the Lunar Gateway that NASA has started developing and end the Space Launch System rocket and Orion spacecraft after two more flights, Artemis II and Artemis III.

“The Budget phases out the grossly expensive and delayed Space Launch System (SLS) rocket and Orion capsule after three flights,” the document states. “SLS alone costs $4 billion per launch and is 140 percent over budget. The Budget funds a program to replace SLS and Orion flights to the Moon with more cost-effective commercial systems that would support more ambitious subsequent lunar missions.”

There are no further details about those commercial systems. NASA has contracted with SpaceX and Blue Origin to develop reusable landers for the Moon, and both of these systems include vehicles to move from Earth orbit to the Moon.

The changes to SLS, Orion, and Gateway have been widely speculated upon in recent months, but seeing them in black and white is still significant. The development of the SLS rocket and Orion spacecraft has been a budget fixture for decades, costing in excess of $3 billion a year for slow progress. The projects have been widely derided as “jobs programs.” However, that is one reason Congress has so fiercely supported them: They provide good-paying, reliable jobs across the country.

During a confirmation hearing last month, a private astronaut tapped by the Trump administration to lead NASA was repeatedly pressed by US senators to commit to flying Artemis II and Artemis III with the SLS and Orion hardware. The nominee, Jared Isaacman, agreed to do so. However, during this hearing, Isaacman made no promises about missions beyond this, nor did members of Congress ask him about Artemis IV or other future missions.

Several sources in the space community, therefore, believe it is indeed plausible that SLS and Orion will be phased out over the next five years in favor of far less expensive commercial rockets and spacecraft. NASA will thus be asked to beat China to the Moon with the legacy systems and then identify more affordable options for future missions to the Moon.

Mars ambitions

One area that will see increased spending under the Trump administration’s proposed budget is human space exploration.

“By allocating over $7 billion for lunar exploration and introducing $1 billion in new investments for Mars-focused programs, the Budget ensures that America’s human space exploration efforts remain unparalleled, innovative, and efficient,” the document states.

Under the Trump administration, NASA will seek to reach both the Moon and Mars. The goal, stated in the document, is to refocus NASA “on beating China to the Moon and putting the first human on Mars.” Unfortunately, there is no information on what these “Mars-focused programs” will be. Some of this new funding would almost certainly go to SpaceX. The company, founded by Trump ally Elon Musk, explicitly focuses on establishing human settlements on Mars.

Although lunar and Mars exploration receive increases, the budget seeks to reduce the agency’s commitment to the International Space Station, while still flying it until 2030. “The Budget reduces the space station’s crew size and onboard research,” the document states. “Crew and cargo flights to the station would be significantly reduced. The station’s reduced research capacity would be focused on efforts critical to the Moon and Mars exploration programs.”

It is likely that Congress will oppose some of these changes, particularly the cuts to science programs and the reduction in activity on the International Space Station. But that story will play out in the coming months as the laborious budget process unfolds.

Eric Berger Senior Space Editor

Eric Berger is the senior space editor at Ars Technica, covering everything from astronomy to private space to NASA policy, and author of two books: Liftoff, about the rise of SpaceX; and Reentry, on the development of the Falcon 9 rocket and Dragon. A certified meteorologist, Eric lives in Houston.

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