A gravity model gives bound past orbits for 12 comets in a fixed JPL hyperbolic sample

We tested past and outgoing energy signs for a fixed public JPL comet sample from 2026-10-24 UTC. The query selected 15 objects with displayed eccentricity at least 1.005. Each had an observation arc of at least 365 days and at least 100 observations. Three objects with fitted gas forces were excluded from the primary test. A Newtonian model of the Sun and eight planet systems gives bound past energy for all 12 remaining nominal paths and all 1,024 correlated orbit draws per object. Eleven past paths reach 250 AU from the model centre of mass. C/2024 L5 instead stops at its previous aphelion at 41.928 AU. C/2002 A3, C/2003 A2, and C/2022 R6 also have bound outgoing energy at 250 AU in every draw. At the element epoch, barycentric energy is bound for only two objects. C/2004 X3 has the weakest past binding, with a central 95% draw interval of 8.74 to 24.50 in units of 10^-6 AU^-1. The package preserves source data, orbit draws, code, figures, source hashes, and numerical checks. This is a dated census and a reusable tool. The method and the known E1 and L5 ejections are prior work. The result is conditional on the saved orbit fits and gravity model. It does not measure the abundance of interstellar objects or include all force errors.

comets · barycentric energy · hyperbolic orbits · JPL SBDB · orbit covariance · C/2024 L5 · C/2004 X3 · reproducible astronomy