The tree · Drive · World event · Root: on the scale of the whole window

A crew lands on Mars and returns to Earth

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The transit-in-months milestone with people aboard: the first round trip proves that a crew can be carried across the inner solar system and back, which is what working rotations to an outer site require. It needs the launch, propellant, and life-support nodes as much as the drive, and it is placed under drive because the transit is the hard part it resolves.

What counts as it having happened

People land on the surface of Mars and return alive to Earth, confirmed by the responsible agency or company and independent tracking of the vehicles.

Settled by: The responsible agency's or company's mission record and independent tracking

Probability, by longevity scenario

baseline2071 ± 8moderate2080strong2095radical2136openno deadline
55%70%85%93%95%

Each number is the chance this resolves yes before that scenario's window closes, given that everything it depends on resolves first. Estimated 2026-09-19.

Why these numbers: One company is building for it; the return leg and two to three years of crew health are the unproven parts, and it is likely by 2095 if the launch architecture works at all.

Notes

Edge drawn at step 7 (2026-09-08): a Mars departure on any current architecture needs refilling in orbit. Life support and shielding make it safer, not possible, so they are not hard dependencies.


Think this node is wrong, missing a dependency, or estimated badly? Open an issue about it, or read how critique gets folded into the tree. The record itself is data/D-drive.toml in the public repository.