NASA’s Quest for Mars Samples: Faster, Cheaper Options Unveiled

NASA is exploring two new strategies for returning samples from Mars to Earth, aiming for a timeline in the 2030s.

Challenges with the Original Plan

The Mars Sample Return program, a collaboration between NASA and the European Space Agency (ESA), was initially ambitious but faced significant challenges. The independent review board’s evaluation revealed that the program could cost as much as $11 billion, which raised alarms within NASA. The projected timeline for sample return was also pushed back from 2031 to 2040, a delay deemed “simply unacceptable” by NASA Administrator Bill Nelson. This prompted a shift in strategy to ensure that the mission remains feasible and timely.

Decision-Making Timeline

NASA has set a clear timeline for making its decision regarding the two proposed strategies by taking into consideration the complexity, cost and mission duration. The agency plans to finalize its choice by the second half of 2026, allowing for sufficient testing and evaluation of the new options. This decision will be pivotal in determining the future of Mars exploration and the feasibility of returning samples within the desired timeframe.

Mars Sample Return Strategies by NASA 

The Perseverance rover, operated by NASA, has been collecting rock and dust samples from Mars since its arrival on the planet in February 2021. These specimens, gathered from Jezero Crater—a location that once hosted an ancient lake and river delta—are considered critical by scientists as they may provide a rare opportunity to determine if life ever existed on Mars.

However, successfully returning these samples to Earth is an extraordinarily challenging task, as it involves answering one of humanity’s most profound questions regarding extraterrestrial life. Both the original mission design and the revised program structure call for the use of multiple spacecraft to land on Mars and transport the collected materials back to Earth.

In April, NASA engaged its various centers and industry partners to propose new methodologies for the streamlined and cost-efficient return of samples to Earth. The agency’s Mars Sample Return Strategic Review team reviewed 11 studies and made recommendations to NASA, which were subsequently adjusted by the leadership.

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

• Sky Crane Method and Commercial Collaboration

The first strategy will be based on the sky crane approach, which has been employed for the entry, descent, and landing of the two rovers that continue to explore Mars. The second strategy will focus on utilizing innovative commercial capabilities and partnerships to deliver a “heavy-lift vehicle” lander to Mars, incorporating designs from companies like SpaceX and Blue Origin, as noted by Nelson.

The challenges posed by Mars to landers are significant, as its thin atmosphere is dense enough to burn a spacecraft that does not have an outer structure with a protective heat shield. At the same time, the atmosphere is insufficiently dense to allow for parachutes to be used alone for deceleration and safe landing.

Engineers devised a system referred to as the sky crane for the deployment of the substantial rover Curiosity, which was instrumental in securing the rover throughout its entry, descent, and landing phases. During the initial descent, the spacecraft was slowed down by a heat shield, parachute, and retrorockets.

The sky crane then carefully lowered the rover to the surface of the red planet via a sturdy cable. Once this operation was completed, the sky crane detached and crash-landed at a location away from the landing site. In 2021, the same design was applied to the landing of Perseverance, and the team was able to capture video footage of the extraordinary descent.

Journey from the Martian surface

Mars Sample Return represents humanity’s first effort to retrieve scientific samples from a planet with potential habitability, according to Fox.

“We want to bring those back as quickly as possible to study them in state-of-the-art facilities,” she said. “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. This will also prepare us to safely send the first human explorers to Mars.”

NASA plans to spend the next year at its Jet Propulsion Laboratory in Pasadena, California, assessing the feasibility of both proposed approaches and addressing their respective engineering challenges. The revised strategies could enable the samples to reach Earth by 2035 at the earliest, or by 2039 at the latest, with estimated costs ranging between $5.5 billion and $7.7 billion—a significant departure from the original budget estimate, as Nelson noted.

Nelson further said. “Pursuing two potential paths forward will ensure that NASA is able to bring these samples back from Mars with significant cost and schedule saving compared to the previous plan. These samples have the potential to change the way we understand Mars, our universe, and — ultimately — ourselves.”

Both alternatives are more efficient compared to the original plan, but they share a comparable design: both necessitate landing a Mars Ascent Vehicle on Mars. This vehicle will be stored with the samples gathered by Perseverance and then launching into space to meet the ESA’s Earth Return Orbiter, which will be orbiting Mars.

The orbiter will then return to Earth, delivering the sample capsule in a manner similar to how asteroid Bennu’s rocks and dust were brought back by the OSIRIS-REX mission, according to Fox. Removing any single component of the original Mars Sample Return design proved to be unfeasible, so efforts were redirected toward simplifying individual elements, Fox explained. 

For instance, NASA decided on a direct sample return to Earth instead of placing the samples in lunar orbit, which would have necessitated another vehicle to retrieve them, Nelson noted. The most significant variation between the approaches lies in the landing mechanism, Fox added.

In both strategies, the Mars landing platform will feature a more compact version of the Mars Ascent Vehicle than originally intended. Additionally, the solar panels on the platform will be substituted with a system capable of providing power and heat during Martian dust storms. According to Fox, this modification will facilitate a quicker return of the samples to Earth.

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

Mars sample return: The path ahead

China has expressed a keen interest in obtaining samples from Mars. The Tianwen-3 mission is anticipated to launch in 2028 with the objective of collecting Martian samples, which are expected to be brought back to Earth by 2031. However, officials have indicated that a launch could potentially occur as early as 2030.

“I don’t think we want the only sample return coming back on the Chinese spacecraft, and that’s just simply a grab and go kind of mission,” Nelson said. “Whereas ours has been a very methodical process to find different samples of different layers showing different ages of material and rocks, and when we bring back those 30 samples, it’s going to give quite a history 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?”

Conclusion

As NASA adapts its strategy, the implications extend beyond mere sample retrieval; the mission is pivotal for advancing scientific knowledge about Mars and preparing for future human missions. The dual approach of exploring both traditional and commercial avenues may also set a precedent for future NASA missions, fostering innovation and collaboration within the space industry.

In light of international competition, NASA’s commitment to scientific integrity and thorough exploration may bolster its standing in global space endeavors. As the agency refines its plans and prepares for potential challenges, the success of the Mars Sample Return mission could have lasting impacts on humanity’s understanding of Mars and the potential for life beyond Earth.