An independent review of NASA’s ambitious mission to return about half a kilogram of rocks and soil from the surface of Mars has found that the program is unworkable in its current form.
NASA had been planning to launch the critical elements of its Mars Sample Return mission, or MSR, as soon as 2028, with a total budget for the program of $4.4 billion. The independent review board’s report, which was released publicly on Thursday, concludes that both this timeline and budget are wildly unrealistic.
The very earliest the mission could launch from Earth is 2030, and this opportunity would only be possible with a total budget of $8 billion to $11 billion.
“MSR is a deep-space exploration priority for NASA,” the report states. “However, MSR was established with unrealistic budget and schedule expectations from the beginning. MSR was also organized under an unwieldy structure. As a result, there is currently no credible, congruent technical, nor properly margined schedule, cost, and technical baseline that can be accomplished with the likely available funding.”
The findings of the independent review, led by Orlando Figueroa, a retired deputy center director for science and technology at NASA’s Goddard Space Flight Center, echo a report published by Ars Technica about three months ago raising serious questions about costs and schedule. The concern expressed by some scientists, including former NASA science chief Thomas Zurbuchen, was that the ballooning cost of Mars Sample Return would cannibalize funding from other science missions.
After the Ars Technica report, some policymakers in the US Senate also expressed serious concerns about the direction of the sample return program.
The mission
Under NASA’s existing plan, the space agency will develop a large “Sample Retriever Lander.” After this vehicle lands on Mars, the Perseverance rover—which has been collecting and storing samples of Martian dust in 38 titanium tubes, each the size of a large hotdog—will bring its samples to the lander.
Once delivered to the lander, these sample tubes will be placed aboard a rocket called the Mars Ascent Vehicle. This rocket is being developed by Lockheed Martin, and it will be stowed inside the lander. After launching from Mars, this rocket will release the “Orbiting Sample container” into Martian orbit, where it would be picked up by an “Earth return orbiter” built by the European Space Agency. This vehicle would carry the samples back to Earth orbit, where they would be released into a small spacecraft to land on the planet about five years after the mission’s start.
As a backup plan, in case Perseverance is unable to deliver the samples to the lander, NASA proposed including two small helicopters like the Ingenuity vehicle to fetch the samples. The independent reviewers said a single helicopter would likely be acceptable.
Why returning samples from Mars is important
The report reaffirms the scientific importance of returning samples from Mars, both for geological purposes and to assess whether life once existed on the red planet, which in its distant past was rather Earth-like, with a thick atmosphere, as well as rivers and lakes.
“MSR represents the critical next step in a strategic program of Mars Exploration spanning the past four decades,” the report states. “US and European orbiters and US rovers have found promising sites where life might once have existed.”
A sample return mission has been a high priority of the scientific community for decades, including being the most highly requested mission in the last two surveys of the National Academies Decadal Survey of Planetary Science report that informs space policy decisions made by Congress and the president.
The reviewers also noted the importance of NASA and the European Space Agency leading the world in space exploration as a hallmark of soft power. China has previously announced plans to launch its “Tianwen-3” sample return mission to Mars as early as 2028 or 2030, which represents a clear challenge to US scientific leadership in Mars exploration.
Many problems to fix
The report says that NASA must do a better job of engaging with the planetary science community to explain its prioritization of the mission and its status as the culmination of a decades-long Mars exploration strategy. Moreover, the reviewers said canceling Mars Sample Return would not free up billions of dollars for other planetary science missions.
“A particular and understandable concern from the community is the impact that MSR may have on the rest of the Planetary Science Division,” the report states. “NASA must address this concern while clarifying and dispelling the notion that cancelling MSR necessarily means greater budgets for everybody else in the Planetary Science Division or even the Mars Exploration Program. Cancellation may also call into question the feasibility of other ambitious sample return efforts envisioned by the planetary science community.”
Because this may be the scientific community’s only near-term shot at studying samples from Mars, the report also says the agency should direct the Perseverance rover to travel outside of Jezero Crater “as soon as feasible.” The aim of such a maneuver would be to obtain “the highest value samples near the crater rim and beyond,” in order to maximize the chance of finding samples that might contain evidence of life.
In all, the report makes more than 20 findings and recommendations that clearly signal to NASA and the mission’s lead field center, the Jet Propulsion Laboratory, that its current plans for the Mars Sample Return mission are broken. As a result, the agency must significantly revamp its plans with the aim toward lowering costs, establishing a reasonable timeline, and maximizing the science potential.
NASA has responded to the report’s release by announcing its own review of the review, saying that this team will make a recommendation by March 2024 regarding a path forward for Mars Sample Return within a balanced overall science program.
Daisy Hips is a science communicator who brings the wonders of the natural world to readers. Her articles explore breakthroughs in various scientific disciplines, from space exploration to environmental conservation. Daisy is also an advocate for science education and enjoys stargazing in her spare time.
