Mars Sample Return
The revised Mars Sample Return strategy does away with a "fetch rover" and its lander, relying instead on the Perseverance rover and helicopters based on Ingenuity. Credit: NASA

Updated March 21 to correct MSR funding and impact of VERITAS.

WASHINGTON — NASA’s effort to return samples from Mars is facing increasing costs that is putting pressure not just on other planetary science missions but also a major heliophysics mission.

NASA, in its fiscal year 2024 budget proposal, requested $949.3 million for Mars Sample Return (MSR), the program that will send missions to Mars to take samples collected by the Perseverance rover and return them to Earth. MSR is a joint effort with the European Space Agency, with NASA leading work on a lander and ESA an orbiter.

That funding is not only a significant increase from the $822.3 million appropriated for MSR in fiscal year 2023, but also a 19% increase from the $800 million NASA projected last year spending on the program in fiscal year 2024. “The budget supports increased requirements in [fiscal year] 2024 to ensure the project continues to make progress towards confirmation and support the earliest feasible launch date,” NASA stated in its full budget request.

NASA’s budget documents also warned that costs will continue to grow. The 2024 request made no changes to future “outyears” projections from last year’s proposal, projecting spending $700 million in fiscal year 2025, $600 million in 2026 and $612.1 million in 2027. The new budget proposal also projected spending $627.6 million in 2028.

“Mars Sample Return costs are expected to increase beyond what is shown in the outyear profile in this budget,” NASA stated in the proposal. “To address this budget challenge, NASA will have to either reduce funding for other activities within the Science Program or descope elements of the Mars Sample Return mission.” That could include removing one of the two sample retrieval helicopters added to the MSR mission concept last year, the document noted.

During a March 13 briefing about the budget proposal, NASA officials provided few details about what is driving those increased costs. Nicola Fox, the new associate administrator for science, said the agency was working through a series of preliminary design reviews (PDRs) for MSR this year before formally confirming the mission.

Agency officials also said little about cost growth during a town hall meeting about MSR at the Lunar and Planetary Sciences Conference March 16. Jeff Gramling, MSR director at NASA Headquarters, said he expected the series of PDRs of elements of the overall campaign to conclude with a system-level PDR in September. That would be followed by a confirmation review as soon as October.

That review, known in agency parlance as Key Decision Point C, is also where NASA sets formal cost and schedule commitments for programs. NASA has not offered an official cost estimate yet for MSR and, asked during the town hall meeting for a “ballpark” estimate, Gramling declined to give one.

“I don’t think I’m in a position right now to give you cost data because we’re still working it through our processes,” he said. That effort includes “grassroots” cost estimates coming through the various reviews as well as a separate independent review planned before the system-level PDR.

However, Mars Sample Return is affecting other agency science programs. NASA cited in its budget request the need “to rebalance work at JPL to ensure that sufficient workforce is available to support high-priority missions in development and formulation” that included MSR as well as Europa Clipper and Psyche as a reason for delaying the VERITAS Venus mission last fall, putting the future of that mission in jeopardy.

Those effects go beyond NASA’s planetary programs. In the fiscal year 2024 budget proposal, NASA said it seeks to suspend work on a major heliophysics mission, the Geospace Dynamics Constellation (GDC). That mission, a recommendation of the 2013 heliophysics decadal survey, would fly a set of six spacecraft that would study the interaction of the upper atmosphere with the magnetosphere and the sun.

NASA had already selected instruments for the mission through a competition and solicited proposals for the six spacecraft. Those proposals were due Feb. 10, with NASA expected to make an award in October to support a launch no later than 2029.

“The Budget proposes to pause GDC development, as continuing development would have required a significant increase in funding at a time when other space science missions, such as the Mars Sample Return mission, also have high budgetary requirements,” NASA said in its budget documents. NASA is seeking only $10 million for the mission, compared to the $49.4 million anticipated for GDC in 2024 from last year’s budget proposal. The 2024 request keeps GDC funding at $10 million in 2025 and 2026, then zeroes it out.

The delay of GDC is a major factor in an overall reduction in heliophysics in the budget, from $805 million it received in 2023 to a request of $750.9 million in 2024. That could be an issue in the Senate, where the appropriations subcommittee that funds NASA is chaired by Sen. Jeanne Shaheen (D-N.H.), whose home state is involved in many heliophysics missions.

“It is not smart to do things like cut the thing that you think is the chair’s highest priority,” said Jean Toal Eisen, vice president of corporate strategy at the Association of Universities for Research in Astronomy and a former Senate appropriations staffer, during a March 16 webinar by the Aerospace Industries Association. “They’re just going to put that back in and take the money from something that you cared about.”

The warnings in the budget proposal for cost increases in MSR “is not a great place to be,” said Casey Dreier, chief of space policy at The Planetary Society, at the same webinar. It increases the risk, he said, of the sample retrieval lander missing its 2028 launch window. “It’s going to be a tough appropriations process to get the money it needs now to keep on that schedule.”

The planetary science decadal survey published in April 2022 endorsed continued work on Mars Sample Return. However, it recommended that if costs increased at least 20% above a projection of $5.3 billion that report adopted, or if costs in any year exceeded 35% of NASA’s overall planetary science budget, the agency should ask the White House and Congress for additional funding to ensure MSR does not “undermine the long-term programmatic balance of the planetary portfolio.”

Using the projections in the NASA budget proposal and going back to when MSR became a standalone program in fiscal year 2021, the agency projects spending at least $5.2 billion on MSR through 2028, a total that will grow from both anticipated cost increases through 2028 and spending needed for MSR after 2028 through the planned return of samples in 2033.

“I think it’s a relatively brittle budget,” Dreier said of the overall NASA budget proposal. “If any one of these programs, or Artemis itself, really goes astray in terms of blowing its schedule or budget, you’re going to see some serious downstream consequences within the agency.”

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...