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    "story_id": "mp-2026-10-27-026",
    "source_story_id": "tmp-story-nearsynchronous-planet-ice",
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    "section": "research",
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    "headline": "A Wandering Noon May Keep an Exoplanet's Water Moving",
    "slug": "a-wandering-noon-may-keep-an-exoplanet-s-water-moving",
    "dek": "Climate simulations of near-synchronously rotating land planets find persistent polar ice but less severe water trapping than fixed-nightside models suggest.",
    "summary": "Climate simulations of near-synchronously rotating land planets find persistent polar ice but less severe water trapping than fixed-nightside models suggest.",
    "body_text": "Planets close to M dwarfs are often modeled with one permanent dayside and one permanent nightside, where ice could lock away much of the water. In compact systems, neighboring planets can make the substellar point librate or circulate over millennia. Using TRAPPIST-1e as a test case, a three-dimensional climate model found a permanent polar reservoir, transient lower-latitude nightside ice that grows with longer synodic days and a persistent ice-free dayside region capable of supporting liquid water. Because ice accumulation may be slower than changes in spin regime, the simulated steady state may never fully form. Adding atmospheric lapse rate and isostatic adjustment to a synchronous model reduced predicted ice buildup by roughly a factor of three.",
    "why_it_matters": "Climate simulations of near-synchronously rotating land planets find persistent polar ice but less severe water trapping than fixed-nightside models suggest.",
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    "importance": 8,
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    "first_published_at": "2026-10-27T09:00:00.000-04:00",
    "modified_at": "2026-10-27T09:00:00.000-04:00",
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        "text": "Climate simulations of near-synchronously rotating land planets find persistent polar ice but less severe water trapping than fixed-nightside models suggest.",
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    "source_ids": [
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    "tags": [
      "exoplanets",
      "climate models",
      "TRAPPIST-1e",
      "habitability"
    ],
    "image_url": null,
    "corrections": []
  },
  "sources": [
    {
      "source_id": "source-2026-10-27-015",
      "title": "arXiv preprint 2610.33884, original v1",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2610.33884v1",
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      "source_type": "primary_research",
      "is_primary_source": true,
      "published_at": "2026-10-25T20:00:00.000-04:00",
      "accessed_at": "2026-10-27T08:18:12.114-04:00",
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    "name": "The Machine Press",
    "url": "https://themachinepress.com",
    "description": "A daily newspaper for the age of artificial intelligence."
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  "cite_this_report": {
    "title": "A Wandering Noon May Keep an Exoplanet's Water Moving",
    "publisher": "The Machine Press",
    "published_at": "2026-10-27T09:00:00.000-04:00",
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