William F. Bottke, David Vokrouhlický, Melissa Dykhuis, Nicolle Zellner (2026), The Planetary Science Journal (vol. 7, no. 7, art. 171) — ARXIV-2606.05036
Key takeaways
- The collisional breakup of the carbonaceous Eulalia parent body near the Jupiter 3:1 resonance, about 800–865 Ma, can plausibly explain the spike in large lunar craters (including Copernicus) and impact-glass ages near 800 Ma. About three-quarters of the family’s fragments drained into the J3:1 over about 150 Myr.
Seeded from the abstract and a skim, before the reading in NOTE-002. What follows is what the work says about itself.
Several lines of evidence point to a surge of large lunar impacts about 800 Ma: the model ages of big craters such as the 93 km Copernicus, and clustering in the ages of Apollo impact glasses. The authors look for a source and point to the Eulalia asteroid family, whose primitive, carbonaceous-chondrite-like parent was disrupted near the J3:1 mean-motion resonance. Their collisional and dynamical simulations send about three-quarters of the fragments into the resonance within about 150 Myr, some directly and some by Yarkovsky drift. From there the fragments reach planet-crossing orbits and raise the bombardment rate on the Moon and the terrestrial planets. The authors speculate that the same shower may connect to biosphere changes on Earth and to a pulse of Martian volcanism.
Standing in the record
Filed by the reading-time triage of 2026-09-25: 11,500 seconds of active reading over 9 sessions in the papers-feed tracker. It was filed Deferred, unread. NOTE-002 is the close reading of 2026-09-25, and it placed the work: Proposed — a careful, well-sourced plausibility model for a hypothesised 800 Ma impact shower, and worth reading as the source model for it. It is unproven: its lunar dates are scaled from a single sample-dated crater (Copernicus), and only Solution 5, the most favourable, is carried forward. Whether the shower happened, which radiometric dating of samples from the other six ~800 Ma craters or a CI-like projectile signature at more than one of them would settle, is THEORY-1195, Proposed; the reading of the model is THEORY-499, Active. The Earth, Mars and Venus material in §7 is self-declared speculation.
When seeded, before the reading in NOTE-002, the entry gave a priority for a deeper reading: low — The owner has already spent a lot of time on it (t = 11500 s). The skim captures the argument, and it has no bearing on the anthology’s ML scope. Revisit only for personal interest in the §7 speculations.
What the seeding asked a deeper reading to check (NOTE-002 is that reading):
- The core claim is plausibility, not proof: a source model that can account for the crater and glass age cluster. It is worth checking how sensitive the timing and magnitude are across Solutions 1–5, and whether the lunar crater ages (Terada et al. 2020) are robust enough to carry a “spike”.
- The Earth and Mars links (§7) are flagged by the authors themselves as speculative prompts for future work, not findings.
- No ML connection. This is planetary science.
Access when seeded: Crossref metadata and abstract for the DOI (journal version online 2026-07-15). The IOP PDF URL in the list returned a Radware bot-captcha page, not the paper. I read the full text from the arXiv preprint 2606.05036v1 (3 Jun 2026, “accepted for publication in The Planetary Science Journal”, 42 pp.), not the typeset journal version. arXiv’s title spells out “800-Million-Year-Old”; the title above is the journal’s. The brief’s description (“Eulalia-family impact/debris shower”) is confirmed.