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  "story": {
    "story_id": "mp-2026-07-17-002",
    "source_story_id": "tmp-feature-1998-sh2-reclassified-comet",
    "edition_id": "mp-2026-07-17-morning-0008",
    "edition_url": "https://themachinepress.com/edition/2026-07-17",
    "position": 2,
    "story_type": "secondary",
    "section": "research",
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    "headline": "The Asteroid Was Quietly Steering Itself",
    "slug": "the-asteroid-was-quietly-steering-itself",
    "dek": "A missed predicted position and weak tail showed near-Earth object 1998 SH2 is an active comet pushed by escaping gas.",
    "summary": "A missed predicted position and weak tail showed near-Earth object 1998 SH2 is an active comet pushed by escaping gas.",
    "body_text": "NASA reclassified 1998 SH2 after its post-flyby position no longer matched an orbit governed by gravity alone. Astrometry showed nongravitational acceleration from escaping gas, while follow-up observations revealed a faint coma and tail. Now designated P/1998 SH2, it is not a newly announced impact threat. The case matters because apparently inert objects can move differently when weak outgassing is present, and planetary-defense orbit models must account for that force.",
    "why_it_matters": "A missed predicted position and weak tail showed near-Earth object 1998 SH2 is an active comet pushed by escaping gas.",
    "limitations": [
      "Now designated P/1998 SH2, it is not a newly announced impact threat."
    ],
    "importance": 9,
    "canonical_url": "https://themachinepress.com/story/mp-2026-07-17-002/the-asteroid-was-quietly-steering-itself",
    "json_url": "https://themachinepress.com/story/mp-2026-07-17-002.json",
    "first_published_at": "2026-07-17T09:00:00.000-04:00",
    "modified_at": "2026-07-17T14:34:04.943-04:00",
    "content_status": "new",
    "is_carryover": false,
    "carryover_reason": null,
    "key_claims": [
      {
        "claim_id": "claim-mp-2026-07-17-002-001",
        "text": "A missed predicted position and weak tail showed near-Earth object 1998 SH2 is an active comet pushed by escaping gas.",
        "source_ids": [
          "source-2026-07-17-002"
        ],
        "qualification": "Now designated P/1998 SH2, it is not a newly announced impact threat."
      }
    ],
    "source_ids": [
      "source-2026-07-17-002"
    ],
    "tags": [
      "comets",
      "near-Earth objects",
      "planetary defense"
    ],
    "image_url": "https://themachinepress.com/issues/2026-07-17/feature-comet-sh2.png",
    "corrections": []
  },
  "sources": [
    {
      "source_id": "source-2026-07-17-002",
      "title": "NASA: Near-Earth asteroid is actually a comet",
      "publisher": "NASA",
      "url": "https://www.nasa.gov/solar-system/comets/nasa-study-finds-near-earth-asteroid-is-actually-comet/",
      "canonical_url": "https://www.nasa.gov/solar-system/comets/nasa-study-finds-near-earth-asteroid-is-actually-comet/",
      "source_type": "official_announcement",
      "is_primary_source": true,
      "published_at": "2026-07-16T12:00:00.000-04:00",
      "accessed_at": "2026-07-17T11:30:57.481-04:00",
      "supports_claim_ids": [
        "claim-mp-2026-07-17-002-001"
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    }
  ],
  "corrections": [],
  "publisher": {
    "name": "The Machine Press",
    "url": "https://themachinepress.com",
    "description": "A daily newspaper for the age of artificial intelligence."
  },
  "cite_this_report": {
    "title": "The Asteroid Was Quietly Steering Itself",
    "publisher": "The Machine Press",
    "published_at": "2026-07-17T09:00:00.000-04:00",
    "canonical_url": "https://themachinepress.com/story/mp-2026-07-17-002/the-asteroid-was-quietly-steering-itself"
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