PASADENA, Calif. — NASA has began work to revise its approach to returning samples from Mars after an independent review concluded the present Mars Sample Return (MSR) architecture has an “unrealistic” budget and schedule.
Sandra Connelly, NASA deputy associate administrator for science, said at an Oct. 20 meeting of the Mars Exploration Program Evaluation Group (MEPAG), an advisory committee, that the agency has convened a team to deal with the recommendations made by an independent review board (IRB) in September.
That independent review found a “near zero” probability that the subsequent major elements of MSR, a sample retrieval lander and Earth return orbiter, can be ready for launch as currently planned in 2027 and 2028. It also estimated MSR costs to be within the range of $8 billion to $11 billion, far higher than previous NASA projections.
“We wish to be sure that we’re taking into account the findings and proposals in order that we are able to structure this program to achieve success and accomplish that inside a balanced budget,” Connelly said.
She is leading a gaggle called the MSR IRB Response Team, or MIRT, that can develop a revised Mars Sample Return architecture. That team, which held a kickoff meeting Oct. 19, includes five subcommittees focused on various technical, science, programmatic and budgetary issues related to this system.
The MIRT will complete its work by the tip of March, she said, offering a revised architecture for MSR. A few of that work began even before the team’s kickoff: Jeff Gramling, MSR director at NASA Headquarters, said one group has been reviewing architectures for the last three to 4 weeks.
The plan he outlined called for choosing two or three alternative architectures this fall for further study, which can include independent cost estimates. One the agency selects a brand new architecture, he said the goal is to get through a confirmation review by late 2024 where NASA makes formal cost and schedule commitments for this system. NASA had previously planned to carry a confirmation review for MSR this fall.
One additional challenge for the trouble is uncertainty about how much funding shall be available for MSR in fiscal years 2024 and 2025 during this effort, a part of broader debates about agency funding. “We don’t know yet what’s going to be appropriated for ’24, so we’re going to should be skinnying down a bit to suit inside ’24 while we pause and step back,” he said.
He didn’t elaborate on the choice approaches to MSR into account. The IRB report listed several that might beat back launches of the lander and orbiter into the 2030s, while incorporating flight-proven technologies just like the “skycrane” landing approach and a rover based on the Mars Exploration Rover that might retrieve samples cached by the Perseverance rover.
There aren’t any plans, agency officials said, for a clean-sheet approach to MSR that might start over with a wholly recent design. “We’re seeking to harvest as much of the work that we’ve done to this point as possible, but additionally stepping back and looking out at ways we are able to reduce cost and increasing resilience,” Gramling said.
The review of other architectures will concentrate on several figures of merit, including total and per-year costs, technical issues and the science value of the revised mission. One example he gave is taking a look at reducing the variety of samples returned, allowing for a smaller Orbiting Sample (OS), the container that might house them. A smaller OS, he noted, could reduce cost and complexity for the general architecture.
Earlier within the meeting, Orlando Figueroa, who chaired the IRB, identified an absence of maturity of the design of the OS as a key problem for MSR. The OS can be launched by a Mars Ascent Vehicle rocket into orbit and be captured by the Earth Return Orbiter, thus impacting the design of each. “It’s an item that interconnects all the components of the architecture,” he said.
NASA officials said they’d work with the European Space Agency, which is answerable for the Earth Return Orbiter and a robotic arm for transferring samples. “Our ESA partners are tightly coupled into all of this and are also bringing their thoughts and concepts to the table,” Gramling said.
Daniel Neuenschwander, ESA’s director of human and robotic exploration, said at an Oct. 19 briefing after an ESA Council meeting that ESA was proceeding with its contributions to MSR. “We’re assessing all options” for MSR, he said, citing an upcoming meeting he had with NASA officials on this system. “It is evident that this assessment must be done along with NASA, but any way forward will then be subject to member states’ decision.”
Each NASA officials and others on the MEPAG meeting said NASA should remain committed to Mars Sample Return despite its current problems. “MSR is clearly, logically the subsequent step in our leadership on Mars,” said Connelly. “It does remain a NASA priority.”
Philip Christensen of Arizona State University, a co-chair of the steering committee that led development of the planetary science decadal survey published in 2022, noted that the report endorsed MSR as its highest scientific priority, while offering recommendations to make sure that it didn’t turn out to be too large an element of NASA’s planetary science portfolio.
“That is something that we must always take very seriously,” he said of that suggestion. “It took a yr and a half of debate and debate to return to this suggestion. It was not achieved evenly, and it really does represent the view of the broad planetary science community of the importance of this project.”