A Proposal to Make Mars Sample Return a Collaborative NASA, ESA, and CNSA Effort

Humanity's self-awareness drives the quest to understand the origins of life. Although Earth history has erased much of our planet's early biological evidence, Mars preserves ancient environments that may hold clues to life's emergence. Robotic explorations have confirmed that Mars once had liquid water and organic compounds, which suggests it was once habitable. However, definitive answers require analysis of pristine samples with advanced techniques in laboratories on Earth, which makes Mars Sample Return (MSR) missions a scientific imperative. NASA's Perseverance rover has begun caching samples, and China's Tianwen-3 mission plans a 2031 return. Yet NASA's MSR program faces cancellation, jeopardizing global efforts. Collaboration among NASA, the European Space Agency, and China's space agency may be the key to retrieving uncontaminated samples before human missions compromise them. A joint mission among these agencies could target the subsurface of an endorheic basin, where minerals such as magnetite may indicate recent vertical fluid cycles from the deep basin. Despite the low surface temperatures, hypersaline brines may transport subsurface microbes toward the martian regolith surface and carry fluids that could deposit authigenic minerals, enhancing preservation of mineral and organic biosignatures. International cooperation would maximize the likelihood of a successful mission, preserve the scientific integrity of samples returned to Earth, and offer humanity a unique opportunity to determine collaboratively whether life exists beyond Earth, fostering unity and shared progress in space exploration.