NASA presents two new plans in the race to return samples from Mars to Earth

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Two new potential strategies for returning crucial samples from Mars to Earth in the 2030s are now on the table, according to NASA.

The proposals present alternatives to the original Mars Sample Return program. Designed by NASA and the European Space Agency, the original plan was deemed unmanageable after an independent review committee predicted it could cost up to $11 billion. The board’s assessment also pushed the expected return date of the samples from 2031 to 2040 — a delay that was “simply unacceptable,” NASA Administrator Bill Nelson reiterated Tuesday.

The agency will decide between the newly proposed strategies, which are intended to reduce complexity, cost and mission duration, in the second half of 2026, Nelson announced during a news conference Tuesday.

The NASA Perseverance rover has been collecting rocks and dust since it landed on Mars in February 2021. Scientists believe these samples — collected from Jezero Crater, the former site of an ancient lake and river delta — may be one of the only ways to determine whether life has ever existed on the red planet.

But returning the samples to Earth, a feat that could answer one of humanity’s biggest questions about the potential for life beyond Earth, is a complex process. Both the original and new architectures for the program include multiple spacecraft that would be used to land on Mars and transport the cache back to our planet.

In April, NASA asked its various centers and industry partners to come up with new plans to get the samples back to Earth in a more streamlined and cost-effective way. The agency’s Mars Sample Return Strategic Review team evaluated 11 of the studies and made recommendations to NASA, which were then further refined by management.

“We are exploring two new landing options,” said Dr. Nicky Fox, associate administrator for NASA’s Science Mission Directorate. “One is to take advantage of technology previously used to land both (the) Perseverance and Curiosity (rovers) on Mars. The other is to take advantage of opportunities from industry.”

The first option will depend sky crane methodused for entry and landing of the two rovers still exploring Mars. The second will use new commercial opportunities and partners to deliver a “heavy-lift vehicle” lander, such as designs from companies SpaceX and Blue Origin, to Mars, Nelson said.

Mars has long posed a challenge to landers because its thin atmosphere is thick enough to burn up a spacecraft not encased in an outer structure with a protective heat shield. But the Red Planet’s atmosphere is also too thin to rely on parachutes alone to slow down and create a safe landing.

For the deployment of the hefty car-sized rover Curiosity, engineers created a system called a sky crane to secure the rover during approach, descent and landing. During the initial descent, a heat shield, parachute and retrorockets slowed the spacecraft.

Then, the sky crane lowered the rover to the surface of the Red Planet using a strong cable. Afterwards, the aerial crane broke off and crashed away from the scene. In 2021, the same design was used to land Perseverance, and the team was actually able to record video of the daring descent.

Mars Sample Return is humanity’s first mission to bring scientific samples from a habitable planet back to Earth, Fox said.

“We want to bring them back as soon as possible to study them in state-of-the-art facilities,” she said. “The Mars Sample Return will allow scientists to understand the geological history of the planet and the evolution of the 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. This will also prepare to safely send the first human explorers to Mars.”

The agency will continue to test the viability of both options and work through the technical challenges of each plan over the next year at NASA’s Jet Propulsion Laboratory in Pasadena, California.

The newly proposed strategies offer the potential to return the samples to Earth as early as 2035, or as late as 2039, and with costs ranging from $5.5 billion to $7.7 billion — a “long cry” from the original figure, Nelson said.

“Pursuing two potential paths forward will ensure that NASA is able to do so 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.”

Although both options are more streamlined than the original plan, they each contain similar architecture, requiring a Mars Ascent Vehicle to land on the Martian surface. That vehicle will be loaded with the samples collected by Perseverance, and then it will lift off and rendezvous with ESA’s Earth Return Orbiter in orbit around Mars.

Then the orbiter will return to Earth and deliver the sample capsule, similar to how rock and dust from the asteroid Bennu was delivered by the OSIRIS-REX mission, Fox said.

There was no easy way to get rid of a single element in the original Mars Sample Return design, so the focus shifted to simplifying each piece, Fox said. For example, NASA opted for a direct return of the samples to Earth rather than placing them in lunar orbit, which would require another vehicle to go and retrieve them, Nelson said. The biggest difference between each option will be the landing mechanism, Fox said.

For both strategies, the platform to land on Mars will carry a smaller version of the Mars Ascent Vehicle than previously planned, and the platform’s solar panels will be replaced with a system that can provide power and heat even during dust storms on Mars. This will allow the samples to be returned to Earth more quickly, Fox said.

“We are very confident that we can return all 30 samples before 2040 and for less than the $11 billion,” Fox said.

Teams at JPL will focus on the engineering design for each plane at the same time over the next year, and one of the challenges will be to make the sky crane 20% larger than the one that landed Perseverance, Fox said. Another challenge is designing a Mars Ascent Vehicle that can survive landing on the Red Planet before launching from it.

The European Space Agency is currently evaluating NASA’s new plans, according to NASA.

Ultimately, President-elect Donald Trump’s incoming administration will be responsible for requesting an adequate budget to support the program — and deciding whether they want to continue with the program at all, Nelson added.

Nelson said he has not discussed the new Mars sample return proposals with Jared Isaacman, the tech billionaire and space criminal Trump has chosen to lead NASA, because all discussions are being handled by the transition team, he said.

“But I think it was a responsible thing to do not to give the new administration only one alternative if they want a Mars sample back, which I can’t imagine they won’t,” Nelson said.

In the past, China has expressed interest in returning samples from Mars as well. The country’s Tianwen-3 mission could launch in 2028 to retrieve the Mars samples, which could be returned to Earth in 2031, although officials have previously shared that they could also launch in 2030.

“I don’t think we want the only test return to come back on the Chinese spacecraft and it’s simply a grab-and-go mission,” Nelson said. “While ours has been a very methodical process … finding different samples of different layers that show different ages of material and rocks, and when we bring the 30 samples back, it will give a whole story of what Mars was like millions of years ago when there was water in the lake. And the big question: Was there life millions of years ago?