A crewed mission lands humans on Mars before 2035.

Question

Six frontier AI models put this at 10% by 14 Sept 2036. Full reasoning from every model.

WillHappen.ai · Accepted Answer

10% — the median of 6 frontier models, resolving by 2036-09-14.

Answer

Gemini (Google): 8% — Orbital refilling, long-duration ECLSS, and Mars descent systems will not clear human-rating hurdles before the 2033 launch window. A 2035 landing requires departing Earth during the late 2033 transfer window, leaving just seven years for uncrewed proof flights. NASA's Artemis program targets lunar landings past 2027, making Mars surface systems an extreme budgetary and operational afterthought. SpaceX landing multiple uncrewed Starships intact on Mars during the 2026 or 2028 windows would be the sole driver to lift odds.

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Claude (Anthropic): 3% — Starship hasn't reached orbit reliably or demonstrated deep-space refueling, both prerequisites for any crewed Mars mission by 2035. SpaceX must first master orbital refueling, long-duration life support, and a Mars-capable heat shield, none demonstrated as of 2026. NASA's own roadmap targets uncrewed Mars sample return and crewed Moon landings first, with no funded crewed Mars mission before the mid-2030s at earliest. Historical spaceflight programs (Apollo, ISS, Shuttle) consistently slipped 5-10+ years from initial targets, and Mars adds orders of magnitude more difficulty than Moon…

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GPT (OpenAI): 11% — It turns on Starship achieving rapid, proven orbital refueling and Mars entry/landing reliability by the early 2030s. NASA's published Artemis-era Mars work is planning, not a funded 2030s landing program; its likely schedule extends beyond 2035. No nation has landed even a crew-capable vehicle beyond the Moon, and Mars EDL plus return life support require many new successes. I would raise this sharply if SpaceX demonstrates repeated tanker transfers and an uncrewed Mars Starship landing by 2030.

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Grok (xAI): 22% — SpaceX must nail Starship refueling, EDL and life-support in the 2028–33 windows. NASA’s Moon-to-Mars path is already slipping past 2035 given Artemis delays and SLS cadence. Musk’s 2029 crewed date has a 0-for-N record versus actual first-flight dates; typical 5–8 yr slips put landing in 2035+. A confirmed uncrewed Starship Mars landing in the 2028 window would be the single biggest upward revision.

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DeepSeek (DeepSeek): 12% — This turns on whether Starship achieves orbital refueling and an uncrewed Mars landing by 2029, which no program currently has scheduled. No crewed Mars landing has ever occurred; the only relevant precedents are Apollo 11 (1969) and Artemis, and Artemis II won't fly crew around the Moon until 2026 at the… Starship still needs orbital refueling demonstrated, a Mars transit habitat, and a 2028-2030 launch window; NASA's own Moon to Mars timeline shows crewed Mars in the… The single development that would move this most is a successful uncrewed Starship Mars landing with orbital refueling by 2028-2029, which would keep a 2033-2035 window…

Answer

Qwen (Alibaba): 3% — Starship must achieve orbital refueling, life support, and Mars EDL in under 9 years—a chain with zero flight heritage today. Starship has not yet demonstrated orbital refueling or crewed flight; each is a prerequisite before any Mars transit vehicle exists. Mars launch windows occur every 26 months (next: late 2026, 2029, 2031, 2033); even the 2033 window requires full stack maturity by ~2031. No crewed Mars EDL system has been tested; the supersonic retro-propulsion and entry mass (~100+ tonnes) far exceed anything flown.

A crewed mission lands humans on Mars before 2035.

SpaceX conducts its first Starship orbital test on or before September 22, 2026.

The Progress 96 cargo spacecraft launches and docks with the International Space Station on September 16, 2026.

NASA's Roman Space Telescope reaches its final operational orbit within three months of its August 30 launch.

A permanent human settlement is established on Mars before 2050.