House and Senate appropriators cut NASA’s budget

House and Senate appropriators have drafted bills that would give NASA slightly less money in 2024 than it received in 2023, rather than the significant increase the administration requested. The Senate Appropriations Committee advanced a commerce, justice and science (CJS) spending bill for fiscal year 2024 on a 28–1 vote during a July 13 markup. That bill funds NASA as well as the National Oceanic and Atmospheric Administration and National Science Foundation, among other agencies. The committee had not released the text of the bill or accompanying report as of early July 14, but a bill summary by the committee stated it provided $25.0 billion for NASA. That is below the $25.384 billion the agency received in fiscal year 2023 and significantly less than the $27.185 billion the agency requested for 2024. That summary did not include a full breakout of funding for the agency in the bill, but it noted that NASA’s exploration programs would get $7.74 billion, less than the $7.97 billion requested for 2024 but more than the $7.47 billion those programs received in 2023. That amount, the summary stated, fully funded Orion, the Space Launch System and ground systems while providing “sufficient funding to continue progress on the Artemis Campaign Development,” including the Human Landing System awards to SpaceX and Blue Origin. In brief comments at the markup, senators said that exploration was their highest priority. The bill funds “the tools for NASA to return astronauts to the moon, including the first woman and person of color, and to maintain U.S. leadership in space,” said Sen. Jeanne Shaheen (D-N.H.), chair of the CJS appropriations subcommittee.

House and Senate spending bills prioritized funding for NASA's exploration program while cutting some science programs. Credit: NASA/Joel Kowsky

“We were able to protect the most important national priority within NASA’s budget, at least in my view, which is to return humans to the moon and maintain our strategic advantage in space,” said Sen. Jerry Moran (R-Kan.), ranking member of the CJS subcommittee.

The bill summary also noted that NASA’s Earth science, astrophysics and heliophysics divisions would be funded at or slightly above 2023 levels. That included restoring a $54 million cut proposed for heliophysics in the 2024 budget request.

The summary was silent on planetary science, but a draft of report language circulating online suggested strong concern by Senate appropriators about the status of Mars Sample Return (MSR). That draft allocated only $300 million for MSR, less than a third of the $949.3 million requested, citing delays and fiscal impacts on other NASA science programs. That comes amid NASA reviews that featured scenarios where the cost of MSR would be roughly double previous agency estimates.

Moreover, that report draft directed NASA to provide the committee with a cost estimate of MSR that would fit in a cap of $5.3 billion, a level recommended by the planetary science decadal survey published last year. If NASA cannot, the draft stated, MSR would be canceled and its funds reallocated to other science mission as well as Artemis.

House appropriators, meanwhile, published their CJS spending bill for fiscal year 2024 ahead of a July 14 subcommittee markup. That bill provides $25.367 billion for NASA in 2024, just under the 2023 spending level but again well below the request for 2024.

The bill would provide full funding for all exploration programs, at $7.97 billion. Science would get $7.38 billion, $880 million below the request and $415 million less than what they received in 2023. The bill did not break out science spending by division.

The funding in both the House and Senate bills are below the request in large part because of the debt ceiling deal reached at the end of May, where Congress and the White House agreed to raise the debt ceiling in exchange for capping non-defense discretionary funding, which includes NASA, at 2023 levels for 2024.

Moran said at the markup that the budget caps affected NASA among other agencies. “They will have significant challenges in continuing all of their programs. I’m disappointed by that,” he said of NASA. “These deep and painful cuts were inevitable under the deal the Speaker [of the House] and the President cut.”

“NASA will have a lot of work to do to figure out how to continue on the programs they are currently planning,” he added.

NASA officials had acknowledged since the passage of the debt ceiling deal that the agency’s funding for 2024 would fall short of its request. “It’s really challenging right now when we look at where we ended up” after the deal, said NASA Associate Administrator Bob Cabana during a July 12 talk at the Future Space 2023 conference.

“The president recommended $27.2 billion. We’re going to end up with less than that as we move forward,” he said. “It’s going to require some hard decisions on our part. It may move things out a little bit longer. It may mean some things have to be stopped.”

Mars scientists look to less expensive missions

On the eve of the release of the planetary science decadal survey likely to place a decreased emphasis on Mars, scientists and NASA officials are planning how to continue exploration of the planet with less expensive missions. The National Academies is scheduled to release the latest decadal survey for planetary sciences April 19. The report will set priorities for planetary science and astrobiology missions for 2023 through 2032. The previous planetary science decadal survey, released in 2011, recommended as its top priority for large, or flagship, missions a rover that could cache samples for later return to Earth. NASA ultimately implemented that recommendation as Mars 2020, with the Perseverance rover currently collecting those samples. Agency officials, speaking at a conference on low-cost Mars mission options in Pasadena, California, in late March, acknowledged it’s unlikely another flagship-class Mars mission will be the top priority of the new decadal survey. Even if it was, the expense of the ongoing Mars Sample Return (MSR) campaign to return the samples Perseverance is caching makes it unlikely the agency could afford another large mission this decade. “In the coming years, MSR is going to be the top priority for NASA relative to Mars and it seems unlikely that the next large-scale mission that the decadal recommends will have Mars as a target,” said Eric Ianson, director of the Mars Exploration Program at NASA Headquarters, in remarks that opened the meeting. “As such, there will not be the budget to develop a flagship-level mission on the order of Perseverance or MRO,” the Mars Reconnaissance Orbiter mission launched in 2005.

NASA's fiscal year 2023 budget proposal would cut the International Mars Ice Mapper mission, the only large Mars mission the agency has under development outside of Mars Sample Return. Credit: NASA

Another factor, he added, was NASA’s push to send humans to Mars as soon as the late 2030s. “Large science missions are probably not going to be the number-one priority,” he said.

Beyond MSR, the only other large Mars mission that NASA had announced was the International Mars Ice Mapper (I-MIM), an orbiter equipped with a radar to look for subsurface ice deposits of interest to both scientists and human exploration planners. The mission would include contributions from Canada, Italy and Japan, with NASA primarily responsible for mission management.

However, just before the conference, NASA’s fiscal year 2023 budget proposal zeroed out funding for I-MIM. “Due to the need to fund higher priorities, including to cover cost growth expected from the Mars Sample Return mission, the budget terminates NASA financial support for the Mars Ice Mapper,” the agency’s budget document stated.

At the conference, Rick Davis, NASA program executive for I-MIM, pressed ahead with a presentation about the mission, including how it could incorporate solar electric propulsion and also deploy a communications relay in Mars orbit to support other missions.

“We have some programs that are overrunning and they’re very high priority programs. That’s the driver for the budget submit,” he said when asked about the budget proposal, adding it would be up to Congress to restore funding for the program.

“The prime driver was overall stress on the budget for multiple projects,” Ianson said. “It’s not unprecedented for the budget to propose a cut to a mission and then Congress puts it back in.”

He sounded skeptical, though, that I-MIM could be revived in that way. “It depends on what kind of advocacy there is,” he said, noting successful efforts to restore funding for astrophysics and Earth science missions. “It’s not as clear to me that a strong advocacy for Ice Mapper exists in Congress.”

At the conference, many were pinning their hopes on smaller missions, both orbiters and landers, that could address key scientific issues. Recent studies, one by the Mars Architecture Strategy Working Group (MASWG) and another by a committee organized by Caltech’s Keck Institute for Space Studies, concluded that low-cost Mars missions were both feasible and useful.

Bruce Jakosky of the University of Colorado, who chaired the MASWG study, said at the conference that there was potential for missions with a total lifecycle cost of between $100 million and $300 million. “We think missions in this range have the potential to do outstanding science,” he said.

There are a couple recent examples, he noted, of such missions. Hope, the Mars orbiter by the United Arab Emirates launches in 2020, has an estimated cost of $200 million. NASA is also funding a smallsat mission to Mars called ESCAPADE with a cost cap of $55 million, scheduled to launch in 2024.

Rob Lillis of the University of California Berkeley, principal investigator for ESCAPADE, cautioned at the conference that his mission might not be applicable to other concepts for low-cost Mars missions. The mission, to study the interaction of the solar wind with the Martian atmosphere, can use low-cost instruments that do not require high data rates. The mission also won a commitment from Rocket Lab, which is supplying the Photon buses for the twin ESCAPADE spacecraft, to stick to the cost cap for the mission.

“$55 million is too low for most realistic missions,” he said. “It’s not the right cost cap for Mars missions in general.”

Jakosky agreed. “The MASWG committee thought that opportunities would really begin to open up to do important science at around $100 million,” he said. Within a projected cost range of $100–300 million, “we have a wide range of capabilities and a wide range of boxes that we can fit in.”