{
  "abstract": "We apply a two-layer thermophysical model, with water sublimating from below a dust-crust with dynamically varying depth, to simulate the water outgassing rate, dust-ejections, and non-gravitational forces and torques of comet 67P/Churyumov-Gerasimenko. The dust-depth is determined at each time-step by the balance of dehydration and subsurface pressure, leading to alternating ejections and crust build-up. This model is the first stage of implementing a fully coupled activity-fallback model that self-consistently incorporates dust-fallback into the ejection depth calculation, but already a number of conclusions can be drawn from these results. The two-layer model with only dehydration and ejections is able to reproduce much of the Rosetta outgassing, dust-ejection data and non-gravitational dynamics, particularly in the comet's more primitive southern terrain. Best agreement is found for nucleus material made up of small aggregates ($d_{agg}\\sim1$ mm) with not-too-high dust-to-ice ratios ($δ\\sim2-8$) and low average strengths ($\\lesssim1$ Pa) that decreases with depth. Disagreements between the observations and model are greatest for the northern-facing and dust-covered terrains, suggesting the importance of surface modification by fallback and material processing here, which will be the subject of investigation in the next paper.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.13230",
  "author_total": 7,
  "authors": [
    {
      "name": "Nicholas Attree"
    },
    {
      "name": "Yuri Skorov"
    },
    {
      "name": "Pedro Gutiérrez"
    },
    {
      "name": "Olivier Groussin"
    },
    {
      "name": "Abhinav Jindal"
    },
    {
      "name": "Raphael Marschall"
    },
    {
      "name": "Samuel P. D. Birch"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/a4s0hgaqsym2e.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.13230",
  "fulltext_url": null,
  "id": "a4s0hgaqsym2e",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.13230",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.EP"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2610.13230",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-09",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/a4s0hgaqsym2e.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:34:34Z",
      "native_id": "2610.13230",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.13230"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.EP",
      "subfield": "planetary"
    }
  ],
  "title": "Towards a coupled activity-fallback model for comets I) 67P/Churyumov-Gerasimenko's water activity from a microphysics model with dynamic dust-depth",
  "title_text": "Towards a coupled activity-fallback model for comets I) 67P/Churyumov-Gerasimenko's water activity from a microphysics model with dynamic dust-depth",
  "type": "preprint",
  "updated_at": "2026-10-30T12:34:34Z",
  "url": "https://research.draconitic.com/paper/a4s0hgaqsym2e",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1093/mnras/stag1930",
      "pid": "6b8vg16ypgz11",
      "relation": "published-as",
      "title": "Towards a coupled activity-fallback model for comets I) 67P/Churyumov-Gerasimenko’s water activity from a microphysics model with dynamic dust-depth",
      "venue": "Monthly Notices of the Royal Astronomical Society"
    }
  ]
}