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    "story_id": "mp-2026-10-26-027",
    "source_story_id": "tmp-story-3i-atlas-monitoring",
    "edition_id": "mp-2026-10-26-morning-0108",
    "edition_url": "https://themachinepress.com/edition/2026-10-26",
    "position": 16,
    "story_type": "dispatch",
    "section": "research",
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    "headline": "The Interstellar Comet Kept Its Color Through Perihelion",
    "slug": "the-interstellar-comet-kept-its-color-through-perihelion",
    "dek": "Fourteen optical epochs and near-infrared follow-up trace 3I/ATLAS across ten months, finding persistent dust but no robust water-ice absorption.",
    "summary": "Fourteen optical epochs and near-infrared follow-up trace 3I/ATLAS across ten months, finding persistent dust but no robust water-ice absorption.",
    "body_text": "Keck and Gemini observations followed interstellar comet 3I/ATLAS from July 2025 through May 2026 with optical imaging, spectroscopy and near-infrared measurements. The team reports no significant mean optical-color change across perihelion, a steeper decline in phase-corrected red-band activity outbound than inbound and extended dust persisting into February. Gas ratios evolved, while the near-infrared spectra did not show water-ice absorption robust to the tested continuum and calibration choices. Dust-loss and surface-layer estimates depend on adopted grain and nucleus assumptions. The campaign is a detailed observational record, not proof of the comet's full composition, and is the text-only report beneath the feature.",
    "why_it_matters": "Fourteen optical epochs and near-infrared follow-up trace 3I/ATLAS across ten months, finding persistent dust but no robust water-ice absorption.",
    "limitations": [
      "Gas ratios evolved, while the near-infrared spectra did not show water-ice absorption robust to the tested continuum and calibration choices.",
      "The campaign is a detailed observational record, not proof of the comet's full composition, and is the text-only report beneath the feature."
    ],
    "importance": 9,
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    "first_published_at": "2026-10-26T09:00:00.000-04:00",
    "modified_at": "2026-10-26T09:00:00.000-04:00",
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        "text": "Fourteen optical epochs and near-infrared follow-up trace 3I/ATLAS across ten months, finding persistent dust but no robust water-ice absorption.",
        "source_ids": [
          "source-2026-10-26-016"
        ],
        "qualification": "Gas ratios evolved, while the near-infrared spectra did not show water-ice absorption robust to the tested continuum and calibration choices."
      }
    ],
    "source_ids": [
      "source-2026-10-26-016"
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    "tags": [
      "3I/ATLAS",
      "interstellar comet",
      "Keck",
      "Gemini"
    ],
    "image_url": null,
    "corrections": []
  },
  "sources": [
    {
      "source_id": "source-2026-10-26-016",
      "title": "arXiv preprint 2610.32972, original v1",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2610.32972v1",
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      "source_type": "primary_research",
      "is_primary_source": true,
      "published_at": "2026-10-23T13:58:04.000-04:00",
      "accessed_at": "2026-10-26T08:26:57.002-04:00",
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  "publisher": {
    "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": "The Interstellar Comet Kept Its Color Through Perihelion",
    "publisher": "The Machine Press",
    "published_at": "2026-10-26T09:00:00.000-04:00",
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