Experts question feasibility of Mars sample return

NASA’s Mars Sample Return campaign remains in planning even as Perseverance continues to collect and store rock and sediment on the Martian surface. NASA said in April 2024 that its then-current design could cost $8 billion to $11 billion and would not return samples until 2040. In January 2025, the agency said it would pursue two competing landing architectures during formulation and choose one later. Space.com reported this week that some experts now doubt the cached samples will ever make it back to Earth, citing toxic dust, engineering complexity and safety concerns for future crews. ### How did NASA get from a flagship science plan to a feasibility debate? NASA said on April 15, 2024 that the agency was resetting the program after an independent review found the existing approach too costly and too slow. Administrator Bill Nelson said at the time that “an $11 billion budget is too expensive, and a 2040 return date is too far away.” NASA also said the revised path would seek lower-cost designs that could return samples in the 2030s. (nasa.gov) A September 2023 Independent Review Board report described Mars Sample Return as “a very complex mission” and examined whether the scope, cost and schedule were aligned. The review asked whether alternative architectures could reduce technical, schedule and cost risk under NASA’s annual budget constraints. (nasa.gov) ### What is actually sitting on Mars right now? Perseverance landed on Mars in 2021 and is the first leg of the sample-return campaign, NASA says. The rover’s job is to collect and cache samples for eventual pickup and return to Earth. NASA’s Mars Sample Return page says the objective is to bring back samples collected by Perseverance in Jezero Crater, where scientists think ancient water once pooled and where possible signs of past microbial life could be preserved. (nasa.gov) NASA says returned samples are a top science priority because laboratories on Earth can do analyses that spacecraft cannot. The agency says those materials could help scientists reconstruct Mars’ geologic and climate history and assess whether the planet ever hosted life. (science.nasa.gov) ### Why are experts raising new doubts now? Space.com reported on August 5 that Martian dust is known to contain hazards including silica and heavy metals, and that planners still face questions about how astronauts and equipment would handle that environment. The report said some experts doubt the samples will ever be returned, tying that skepticism to dust toxicity, mission logistics, engineering timelines and crew-safety concerns. (nasa.gov) NASA’s own public descriptions underscore the technical challenge. The agency said in April 2024 that the mission would require safely landing near the samples, launching a rocket from another planet and transporting the material more than 33 million miles back to Earth. Nelson said that sequence would be “one of the most complex missions NASA has ever undertaken.” (space.com) ### What plan is NASA working on now? NASA said on January 7, 2025 that it would carry two landing options through formulation rather than commit immediately to one architecture. One option would use the sky-crane landing method flown on Curiosity and Perseverance; the other would rely on newer commercial landing capabilities. Both approaches would include a landed platform carrying a smaller Mars Ascent Vehicle. (nasa.gov) Nicky Fox, NASA’s associate administrator for science, said then that the agency wanted to bring the samples back “as quickly as possible” for study in Earth laboratories. NASA said it expected to confirm the program and its design in the second half of 2026. ### What happens next if the samples are ever to leave Mars? (nasa.gov) NASA’s current mission page describes Mars Sample Return as a proposed campaign with the European Space Agency to retrieve Perseverance’s tubes from Jezero Crater and carry them back to Earth. The next formal milestone NASA has publicly named is confirmation of a single program design in the second half of 2026, after which cost, schedule and hardware choices would be set more firmly. (nasa.gov)