v2.2.0

Earlier version of the analysis for Edwards (2026), "Constraints on the Origin of the Asteroid Belt's Compositional Gradient from Debiased Taxonomic Data", which cites v2.6.3. v2.3.0 differs only in its input, the catalog release data-2026-09-29c (225 more unclassified bodies); every table and fraction is identical (see its notes).

New input. v2.2.0 analyses the AsteroidCatalog release data-2026-09-27 (1,568,641 bodies, data contract 1.6.0). belt-gradient fetch downloads it by tag and checks the sha256 its manifest lists. The method is unchanged from v2.1.0.

What the new release changes, checked body by body against data-2026-09-26b:

• 751 more main-belt bodies (1,442,785 → 1,443,536), all without a classification: they join the assumed-albedo tier (1,200,767 → 1,201,518). No body left the main belt.
• For every main-belt body in both releases, class, orbit, absolute magnitude, diameter and albedo are identical.
• Data contract 1.6.0 changes the class densities behind estimated masses: an X-type with a measured albedo now takes the P, M or E density that its albedo indicates, one without takes their mixture, and the P and Q densities are lower. This moves the masses of 15,455 classified bodies, all P, Q or X types.

Results. Every zone fraction, crossover, orbit test, bootstrap interval, mass C-fraction and table is identical to v2.1.0. In summary.json:

• the measured share of classified mass: 0.9397 → 0.9514
• mass shares of classified mass: Ceres 0.3851 → 0.3899, Vesta 0.1063 → 0.1076, Pallas 0.0842 → 0.0853, Hygiea 0.0337 → 0.0341; the inner belt's S share of all classified mass 0.8908 → 0.8912
• the family fraction under the one-step extension: 0.2431 → 0.2429

Three figures change: completeness (the faint-end curves), mass by zone (the P- and X-type bars), and circularity (the legend's n).

Figure fix. The mass-by-zone figure puts its legend under the two panels. In the right panel it covered the outer zone's total-mass label.

Headline results (unchanged, results/summary.json):

• S/C crossover: 2.84 AU raw, 2.41–2.47 AU once families are collapsed and the sample is limited by size. The 10–90% transition is 1.4–1.5 AU wide, wider than the belt.
• Inner-belt C/(S+C): 0.25 raw, 0.39–0.53 corrected.
• Orbit test: one of eight KS tests passes Bonferroni, outer-belt sin i (p = 0.0060). With the one-step family extension none does (smallest p = 0.011), so it is read as family halos.

No API changes.