The tree · Biology · World event · Root: on the scale of the whole window
People live for a year in a spinning habitat with Earth-normal gravity
The full version of the habitat route: a structure large enough (roughly a hundred metres or more in radius, spinning about three times a minute) that its occupants feel Earth's gravity and need no adaptation at all. If partial gravity turns out to be unlivable, this is the only route to a Belt, and it is the route some space futurists prefer anyway.
What counts as it having happened
A rotating habitat produces at least ninety percent of Earth's gravity at its living level and is continuously occupied by at least ten people for twelve months, confirmed by the operator and independent tracking.
Settled by: The operator's records and independent orbital tracking
Probability, by longevity scenario
| baseline2071 ± 8 | moderate2080 | strong2095 | radical2136 | openno deadline |
|---|---|---|---|---|
| 25% | 32% | 45% | 70% | 80% |
Each number is the chance this resolves yes before that scenario's window closes, given that everything it depends on resolves first. Estimated 2026-09-08.
Why these numbers: Given a spin demo and hundred-metre assembly, an Earth-gravity habitat is a matter of money and motive; one in four by 2071 because both are large and the partial-gravity route may make it unnecessary.
Notes
Edge drawn at step 7 (2026-09-08): a habitat with Earth-normal gravity is a hundred-metre-class structure, so it needs orbital assembly to have been done at that scale.
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The record itself is data/B-biology.toml in the public repository.