NASA officials have announced a new two-pronged approach to the troubled Mars Sample Return mission, which aims to bring soil samples collected by the Perseverance Rover back to Earth by 2035.
The return of the samples to Earth will provide potentially crucial insights into the geological history of the Red Planet, helping to prepare for human exploration that will occur there in the decades ahead and to “help NASA’s search for signs of ancient life,” the space agency said in a statement on January 3.
In 2022, an ambitious mission update fueled by tantalizing discoveries made by Perseverance set an even earlier return date of 2033. However, according to NASA Director Bill Nelson, the program’s budget overruns and increasingly delayed completion date led the agency to look for a new, more economically viable solution.
“The cost began to accelerate to the point that earlier this past year, it was thought that it could be as much as $11 billion, and you would not even get the samples back until 2040,” Nelson explained at a Tuesday media briefing outlining the new proposals. “That was just simply unacceptable.”
The agency responded in September 2024 with a new directive by accepting 11 scientific studies from within the NASA science community and its industry partners, proposing cheaper and more timely alternatives than the previous plan. Following an analysis of the options, the agency’s Mars Sample Return Strategic Review team recommended the dual path forward announced by NASA.
Two Potential Paths to Bring Back Potential Proof of Life on Mars
In a written statement outlining the new Mars Sample Return mission directive, the agency offered a few details on the two paths currently under consideration. The first is a slimmed-down version of the original plan that uses the crane landing method employed for both the Curiosity and Perseverance rovers. The helicopters have been removed in the new version, and a simplified lander/rover designed to retrieve the samples is proposed to replace them.
In the second version of the plan, NASA’s private contractors will contribute the hardware and mission parameters that also meet NASA’s budget and timeline considerations. Although specific details about the private contractor option were not immediately available, NASA contractor Space X is already developing its Starship vehicle to take astronauts and equipment to the Moon and Mars.
Both new proposals will still utilize the Mars Ascent Vehicle (MAV) from the initial plan to launch the samples into orbit for transport to Earth. However, the revamped MAV will be powered by a radioisotope power system instead of solar panels. NASA says this change will offer the vehicle more consistent power than the previously proposed panels, especially at night and during dust storms.
Once in orbit, the lander will be captured by the European Space Agency’s Earth Return Orbiter. Next, the lander will transfer the samples that may contain proof of life on Mars to a part of the return orbiter designed to receive up to 30 sample tubes. Lastly, the samples will be stored within the vehicle’s capture, containment, and return system and flown to Earth.
According to NASA, the newly redesigned sample loading system on the lander offers cost savings and reduced mission time because it “simplifies the backward planetary protection implementation by eliminating the accumulation of dust on the outside of the sample container.”
Mars Samples Could ‘Change the Way We Understand Our Universe’
Whichever route they choose, NASA’s mission scientists say it is vital that we return the samples to Earth to analyze them in a laboratory for proof of life on Mars. They also argue that bringing those samples home would complete the final, critical steps of the Perseverance team to collect and prepare samples from locations where life was most likely to have thrived in the red planet’s ancient past.
“NASA’s rovers are enduring Mars’ harsh environment to collect ground-breaking science samples,” said Nicky Fox, the leader of NASA’s Science Mission Directorate. “We want to bring those back as quickly as possible to study them in state-of-the-art facilities.”
“Mars Sample Return will allow scientists to understand the planet’s geological history and the evolution of climate on this barren planet where life may have existed in the past and shed light on the early solar system before life began here on Earth,” Fox added. “This will also prepare us to safely send the first human explorers to Mars.”
Although NASA is currently evaluating both options, it expects to confirm its final choice and overall design sometime in the second half of 2026. Both plans propose a final sample return date in 2035. The ESA is also evaluating NASA’s plans and is still expected to be a primary partner in the mission.
“Pursuing two potential paths forward will ensure that NASA is able to bring these samples back from Mars with significant cost and schedule savings compared to the previous plan,” Nelson said. “These samples have the potential to change the way we understand Mars, our universe, and – ultimately – ourselves.”
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.