Three missions in one year reach the asteroid belt within twelve months of leaving Earth

The Tier 3 criterion in propulsion terms: transit fast enough that people go out there to work. A Slow Expanse needs ships that reach the Belt in months rather than years, often enough that going is routine. Nuclear propulsion is one way to get there and high-power solar-electric propulsion is another; chemical rockets with refilling in orbit take well over a year to the Belt on the usual path. This is the function step, written so that any propulsion counts (the function-over-route rule, docs/methodology.md), with the two propulsion routes under it.

The test: what counts as it having happened

In one calendar year, at least three separate missions, crewed or cargo, each arrive at a destination in the main asteroid belt or farther from the Sun (rendezvous with, orbit or land on a body at least 2.1 astronomical units from the Sun, or on a moon of such a body; a flyby does not count) within twelve months of leaving Earth orbit, by any propulsion, confirmed by the operators and independent tracking of the vehicles.

Settled by: Operators' mission records and independent tracking

The odds, by how long I live

baselineto 2071 ± 8	moderateto 2080	strongto 2095	radicalto 2136	openno deadline
50%	62%	76%	87%	91%

Each column is a different guess at how long I live, from current trends (baseline) to open-ended. The number is the chance this happens before that deadline, assuming everything it depends on happens first. As of 2026-09-25.

Why these numbers: First estimate, 2026-09-25, proposed by Claude with the node and accepted by John 2026-10-02. Given that some fast propulsion is already in routine use somewhere in the inner solar system, the question is whether anyone sends three ships a year to the Belt on it; that needs a reason to go, which the Belt tier's other steps (an outer site, a product sold) are about. Even odds by 2071. One thing it can cost: a world whose outer site is Mars and whose fast ships go only there does not meet this step.

What this one is worth

If this happened tomorrow and nothing else changed, the chance that I live and work off Earth by 2071 goes from 0.5% to 0.5% (too small to tell apart from chance). If it turned out no, the same number goes to 0.0% (−0.5 points).

Longevity scenario	baseline2071 ± 8	moderate2080	strong2095	radical2136	openno deadline
The headline as it stands	0.5%	1.2%	3.8%	11%	15%
If this settled yes now	0.5%	1.4%	4.1%	11%	16%
If this settled no now	0.0%	0.0%	0.0%	0.0%	0.0%

This is what the site says in advance, before the thing happens. When it does, the ledger entry that records it quotes this figure beside what actually followed, so a reader can see whether the prediction held. Worked out at the run 2026-10-11-scan by holding this step at each outcome in turn and playing the whole tree out again, 20,000 times per scenario. That is a throw of the dice, so a move smaller than about 0.10 points is inside the noise rather than a finding.

The last check

Once a week the tree is read against the news, node by node, against the test above. Open a line to see what that week held. Every check ever made on this node is on the Radar page.

• 2026-10-04 Nothing new

  Starship Flight 14 reached orbit on 2026-09-28 and was cut short, but no mission reached the asteroid belt within twelve months of leaving Earth; Psyche arrives in 2029 after a multi-year cruise.

Notes

Added 2026-09-25 under candidate 6 of docs/proposal-function-over-route-2026-09-25.md, approved by John 2026-09-25, with the pass counting as the review a tier change needs. Replaces D-nuclear-propulsion-in-routine-use in Tier 3's requirements (data/tiers.toml); the tier's definition now reads 'transit fast enough that people go out there to work'. The criterion's numbers (under twelve months to the Belt, three missions a year, crewed or cargo) were set in the handoff; the 2.1-astronomical-unit edge of the Belt and the flyby exclusion are Claude's drafting.

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