Anyone hoping for a clear path forward this year for NASA’s imperiled Mars Sample Return mission will have to wait a little longer.
The agency has settled on two potential strategies for the first effort to bring rock and soil from another planet back to Earth for study, NASA Administrator Bill Nelson said Tuesday: It can either leverage existing technology into a simpler, cheaper craft or turn to a commercial partner for a new design.
But the final decision on the mission’s structure — or whether it should proceed at all — “is going to be a function of the new administration,” Nelson said. President-elect Donald Trump will take office Jan. 20.
“I don’t think we want the only [Mars] sample return coming back on a Chinese spacecraft,” Nelson said, referencing a rival mission that Beijing has in the works. “I think that the [Trump] administration will certainly conclude that they want to proceed. So what we wanted to do was to give them the best possible options so that they can go from there.”
The call also contained words of encouragement for NASA’s Jet Propulsion Laboratory in La Cañada Flintridge, which leads the embattled mission’s engineering efforts.
“To put it really bluntly, JPL is our Mars center in NASA science,” said Nicky Fox, associate administrator of the Science Mission Directorate. “They are the people who landed us on Mars, together with our industry partners. So they will be moving forward, regardless of which path, with a key role in the Mars Sample Return.”
In April, after an independent review found “near zero probability” of Mars Sample Return making its proposed 2028 launch date, NASA put out a request for alternative proposals to all of its centers and the private sector. JPL was forced to compete for what had been its own project.
The independent review board determined that the original design would probably cost up to $11 billion and not return samples to Earth until at least 2040.
“That was just simply unacceptable,” said Nelson, who paused the mission in late 2023 to review its chances of success.
Ensuing cuts to the mission’s budget forced a series of layoffs at JPL, which let go of 855 employees and 100 on-site contractors in 2024.
The NASA-led option that Nelson suggested Tuesday includes several elements from the JPL proposal, according to a person who reviewed the documents. This leaner, simpler alternative will cost between $6.6 billion and $7.7 billion, and will return the samples by 2039, he said. A commercial alternative would probably cost $5.8 billion to $7.1 billion.
Nelson, a former Democratic U.S. senator from Florida, will step down as head of the space agency when Trump takes office. Trump has nominated as his successor Jared Isaacman, a tech billionaire who performed the first private space walk, who must be confirmed by the Senate.
NASA has not had any conversations with Trump’s transition team about Mars Sample Return, Nelson said. How the new administration will prioritize the project is not yet clear.
“It’s very uncertain how the new administration will go forward,” said Casey Dreier, chief of space policy for the Planetary Society, a Pasadena nonprofit that promotes space research. “Cancellation is obviously still on the table. … It’s hard to game this out.”
Planetary scientists have identified Mars Sample Return as their field’s highest priority in the last three decadal surveys, reports that the National Academies of Sciences, Engineering, and Medicine prepare every 10 years in order to advise NASA.
Successfully completing the mission is “key for the nation’s leadership in space science,” said Bethany L. Ehlmann, a planetary scientist at Caltech in Pasadena. “I hope the incoming administrator moves forward decisively to select a plan and execute. There are extraordinary engineers at JPL and NASA industry partners eager and able to get to work to make it happen.”
