NASA–ESA · In Development
The most ambitious robotic space mission ever conceived — retrieving Perseverance's cached rock and soil samples from Jezero Crater and delivering them to Earth laboratories. If successful, these will be the first samples ever returned from Mars, potentially answering whether life ever existed on another planet.
While Mars rovers carry increasingly sophisticated instruments, Earth-based laboratories are orders of magnitude more capable. A single university geology lab has more analytical power than every instrument ever sent to Mars combined. Returned samples could be studied with electron microscopes, mass spectrometers, synchrotron X-ray facilities and techniques that haven't been invented yet. If biosignatures exist in Jezero Crater's ancient lake sediments, laboratory analysis is the most likely way to confirm them definitively.
Perseverance has collected dozens of rock and soil samples using its coring drill, each sealed in titanium tubes about the size of a marker pen. Some tubes were deposited on the Martian surface at a location called Three Forks as a backup cache, while others remain aboard the rover. The samples span Jezero Crater's geological history: ancient lakebed sediments, delta deposits, igneous rocks from the crater floor, and even atmospheric gas samples.
The Mars Sample Return campaign involves multiple spacecraft working in sequence. The current baseline has Perseverance itself delivering its sample tubes to the retrieval lander (rather than using a separate fetch rover). A Mars Ascent Vehicle (MAV) — the first rocket ever launched from the surface of another planet — would loft the samples into Mars orbit. ESA's Earth Return Orbiter would capture the sample container in orbit and bring it back to Earth, where it would land in the Utah desert under parachute for containment and laboratory transfer.
The campaign has faced significant cost and complexity challenges. An independent review in 2023 estimated costs exceeding $8–11 billion and a return date potentially slipping to the late 2030s. NASA has solicited alternative architectures from commercial providers to reduce cost and accelerate the timeline. Despite the challenges, MSR remains a top priority for planetary science — the 2023–2032 Planetary Science Decadal Survey ranked it as the highest-priority flagship mission.
A NASA lander that touches down near Perseverance. The rover drives to the lander and deposits its sample tubes. The lander also carries the Mars Ascent Vehicle. Landing precision requirements are among the most demanding in Mars exploration history.
The first rocket to launch from the surface of another planet. A two-stage solid-fuel rocket that lofts the sample container (~0.5 kg) into a 300–400 km Mars orbit. Must survive months on the Martian surface before ignition — a completely novel engineering challenge.
Built by ESA (European Space Agency), this solar-electric propulsion spacecraft captures the sample container in Mars orbit using a rendezvous-and-capture system. It then performs the 9-month transit back to Earth. Houses the Earth Entry Vehicle for final descent.
The returned samples will be treated with extraordinary biosafety protocols. A dedicated Sample Receiving Facility (SRF) — similar in concept to a BSL-4 laboratory — will perform initial analysis before distributing material to research institutions worldwide for decades of study.