NASA still wants to bring samples back from Mars being gathered by the Perseverance rover, but ballooning costs for the return trip to Earth under a limited budget that would force years of delays is prompting the agency to seek out a cheaper, faster plan. 

“We are committed to retrieving the samples that are there, at least some of those samples,” NASA Administrator Bill Nelson said during a news conference Monday. “This bottom line is that $11 billion is too expensive and not returning samples until 2040 is unacceptably too long.”

He noted that Perseverance, which launched from Cape Canaveral in 2020 on a ULA  Atlas V and arrived at Mars in 2021, continues to collect what will be more than 30 rock and soil samples, some of which will be in the rover and others left in preplanned spots on the surface.

The original Mars Sample Return (MSR) plan called for a new spacecraft to land on Mars with an ascent vehicle that would take the samples to a rendezvous with a second spacecraft launched by the European Space Agency orbiting Mars. It would then make the return flight home to Earth.

The mission has been a priority for NASA after its top ranking in the latest Planetary Science and Astrobiology Decadal Survey, which helps guide NASA science mission choices.

Nelson pointed out that the survey suggested the entire mission should only cost somewhere between $5 and $7 billion, but under the working plan, cost projections by independent reviews saw that rising to between $8 and $11 billion.

NASA spent $822 million on the sample return mission in fiscal 2023, but with a congressional deal in place for the next two fiscal years that limited NASA’s overall budget, MSR, which was being managed out of NASA’s Jet Propulsion Laboratory, was either going to have to gobble up most of NASA’s Science Mission Directorate’s budget, or undergo a drastic makeover.

Nelson said sticking with the plan “would cause NASA to have to cannibalize other programs.”

That includes summer 2028 launch targets for both the Near-Earth Object (NEO) Surveyor and the Dragonfly rotorcraft mission to Saturn’s moon Titan, but also previously announced DaVinci and Veritas missions to Venus that had been in limbo.

JPL already laid off more than 500 employees with the expected budget crunch, and with the shift, NASA said it only expects to fund existing MSR planning at $310 million for fiscal 2024 and $200 million in fiscal 2025, focusing on parts of the plan that it expects will remain part of the revamped approach.

“I take it back to the old country boy saying that you can’t put 10 pounds of potatoes into a five-pound sack, and so we are trying to take the budget that we have been constrained with,” Nelson said, noting NASA received more than $2.5 billion less than what it had asked for, and that includes nearly $1 billion less for the Science Mission Directorate. “We’re trying to figure out how to make this go forward without hurting (other science missions) that are so important to the future of our planetary science program.”

So the new plan is to seek mission pitches by this fall from not just JPL, but all of NASA’s centers as well as industry partners. The goal is to figure out a new approach to MSR that could bring the samples home in the 2030s, and under the original budget projections.

It still aims to keep its partnership with the ESA, which is still on track to launch its orbiting Mars spacecraft by the end of the decade.

When Perseverance was launched, the MSR mission targeted as early as 2031 for the samples to make their way back to Earth. The most recent independent review released in September 2023 became a serious reality check of the rising costs and timeline that prompted NASA’s overhaul.

“Our response does include an updated mission design, that has reduced complexity, improved resiliency and risk posture as well as strong accountability and coordination,” said NASA’s Nicky Fox, head of the Science Mission Directorate.

She said the goal is to use existing technology as opposed to relying on something that needs to be developed, but calling it “out-of-the-box options.”

When asked if come this fall the new pitches don’t improve the time and cost significantly, and while knowing there’s no simple solution, Nelson remained optimistic.

“We’re definitely going to try, but I suspect if folks at NASA and our contractors and our centers and JPL, they put their minds to it, you know, these are folks who can figure out rather difficult things,” he said. “I’m going to reserve the time till this fall, and let’s see what we have.”