Mars rocks are a science prize that the US can’t afford to lose
NASA does difficult, inspiring and ambitious things – and it does them, in the immortal words of President John F. Kennedy, because they are hard. NASA’s most ambitious planetary project yet is Mars Sample Return, a partnership with the European Space Agency to robotically collect and bring back to Earth scientifically invaluable rocks from Mars for study in labs here. But the mission is in trouble.
Mars Sample Return represents the culmination of decades of planning by the planetary science community, and it has been the top-ranked scientific priority of the last two Decadal Surveys of the National Academies of Sciences, Engineering, and Medicine. The surveys are exhaustive reports written by dozens of scientists over many months, designed to help NASA chart its agenda in 10-year increments.
There are compelling reasons to bring samples back from Mars.
The technologies required for retrieving soil and rocks from Mars will underpin those needed for NASA’s Moon to Mars initiative, a grand plan to eventually send humans to Mars and bring them safely home. And successfully retrieving study samples from Mars would reaffirm the United
States’ leadership in robotic space exploration at a time when China is eyeing that very same prize.
The samples have the potential to revolutionize our understanding of the Red Planet’s geological history and whether it might ever have hosted life. They will offer vital information about the environment Mars astronauts would encounter, and they will give us brand-new insight into the processes that shape planets generally. Just as scientists have done with 50year-old Apollo moon samples, what is collected now can be studied for decades to come, making use of analytical capabilities yet to be invented and representing a scientific gift that keeps on giving.
The first phase of Mars Sample Return has begun. In February 2021, the rover Perseverance landed on Mars tasked with collecting air, rock cores and soil that would ultimately be returned to Earth. Equipped with a sophisticated sampling system, Perseverance has filled 23 of its collection tubes and has 15 more.
The envisioned next phase is sending a Sample Retrieval Lander to rendezvous with Perseverance, transferring the samples and then launching them into space, to be picked up by an Earth Return Orbiter furnished by ESA.
Yet how, when, or even if those next phases will happen is far from certain.
Faced with rising costs, NASA commissioned an independent review of the entire program in 2023. The review didn’t pull punches, finding that the likely cost of the project had ballooned, its organizational structure wasn’t working, and that NASA hadn’t effectively communicated to the science community or the public why the massive effort was worthwhile in the first place. Despite that, the review emphasized that the scientific and geopolitical value of Mars Sample Return couldn’t be overstated, and that the project could be made affordable.
Still, the Senate threatened to reduce the project’s budget substantially and even cancel it outright, which starkly contrasted with the House’s proposal to support the program fully. Congress now proposes to fund it at some level, but this uncertainty has driven
NASA to “ramp back” its Mars Sample Returnrelated activities.
Congress has a choice: It can turn its back on Mars Sample Return or commit to funding the boldest robotic planetary science effort humanity has yet undertaken.
Let’s be clear: Abandoning the project would not only sacrifice work already underway, it would be a major blow to the Decadal Survey process, hurting not just planetary science but the other science communities that have relied on the survey process for establishing scientific and funding priorities going as far back as the 1960s.
Congress should sufficiently fund NASA to realize the generational goal of returning to Earth samples from Mars.
Mars Sample Return is hard, but that isn’t its problem. For NASA, and for the United States, it’s perhaps the single best reason to do it.
Paul Byrne is an associate professor of earth, environmental and planetary science at Washington University in
St. Louis. Vicky Hamilton is an institute scientist at Southwest Research Institute in Boulder, Colorado.