NASA plans to recover possible signs of life from Mars

NASA plans to recover possible signs of life from Mars

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New strategies for returning Mars samples

According to NASA, there are now two new potential strategies for returning important samples from Mars to Earth by the 2030s.

These proposals represent alternatives to the original Mars Sample Return Program The program, designed by NASA and the European Space Agency (ESA), was deemed unmanageable after an independent review that projected costs of up to $11 billion. Additionally, the estimated sample return date was pushed back from 2031 to 2040 — a delay that NASA Administrator Bill Nelson called “simply unacceptable.”

Decision by the end of 2026

The agency will decide between the newly proposed strategies aimed at reducing complexity, cost and mission duration by the second half of 2026, Nelson announced during a news conference.

The NASA Perseverance rover has been collecting rocks and dust since landing on Mars in February 2021. Scientists believe these samples - which come from the Jezero crater, which was once an ancient lake and river delta region - may represent one of the few ways to find out whether Life ever existed on the red planet.

Complexity of sample return

Returning the samples to Earth is a complex matter that could provide answers to humanity's biggest questions about the possibility of life beyond Earth. Both the original and new programs involve multiple spacecraft used to land on Mars and transport the samples back to Earth.

In April, NASA asked various centers and industry partners to develop new plans to return the samples in a more efficient and cost-effective manner. The agency's Mars Sample Return Strategic Review team evaluated 11 of the studies and made recommendations, which were then further refined by leadership.

Two new landing options

“We are exploring two new landing options,” said Dr. Nicky Fox, deputy administrator of NASA's Science Mission Directorate. "The first is based on technologies previously used to land both the Perseverance and Curiosity rovers on Mars. The second draws on options from industry."

The first option uses the Sky crane method, which was used for the entry, descent and landing of the two rovers. The second option will leverage new commercial opportunities and partners to create a "heavy-lift vehicle" lander, such as designs from companies like SpaceX and Blue Origin, to Mars, said Nelson.

The challenges of the Martian atmosphere

Mars has long posed a challenge for landers because its thin atmosphere is thick enough to burn spacecraft without a protective heat shield. Additionally, Mars' atmosphere is too thin to rely solely on parachutes to provide a safe landing approach.

To derive the heavyweight Curiosity rover, engineers developed a system called a sky crane to secure the rover during entry, descent and landing. During the initial descent, a heat shield, parachute and recoil rockets slowed the spacecraft.

The Sky Crane then lowered the rover to the surface of the red planet using a strong cable. The sky crane then separated and landed uncontrollably near the site. In 2021, the same design was used to land Perseverance and the team was even able to Record video of the bold descent.

Mission to retrieve Mars samples

The Mars Sample Return mission is the first of its kind to bring scientific samples from a habitable planet back to Earth, Fox explained. “We want to bring these samples back as quickly as possible to be examined in state-of-the-art facilities,” she added. "The Mars Sample Return will allow scientists to understand the planet's geological history and explore the evolution of the climate on this hostile planet where life may once have existed. Additionally, it will shed light on the early solar system, before life began here on Earth, and help us safely send the first human explorers to Mars."

Tests and technical challenges

The agency will test the feasibility of both options and address the technical challenges of each plan next year at NASA's Jet Propulsion Laboratory in Pasadena, California. The newly proposed strategies offer the possibility of returning the samples to Earth as early as 2035 or no later than 2039, at a cost ranging from $5.5 billion to $7.7 billion — "a big difference" from the original figures, Nelson said.

“Pursuing two possible paths will ensure NASA is able to return these samples with significant cost and time savings compared to the previous plan,” Nelson explained. “These samples have the potential to change our understanding of Mars, our universe and ultimately ourselves.”

The way into the future

While both options are designed to be more efficient than the original plan, they each feature similar architecture, requiring a Mars Ascent Vehicle to land on the Martian surface. This vehicle will be loaded with samples collected by Perseverance, from where it will lift off and rendezvous with ESA's Earth Return Orbiter in Mars orbit.

The orbiter will then be na