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    "headline": "Thirty Metal-Poor Stars Became Precision Benchmarks",
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    "dek": "Fifteen eclipsing binaries yielded masses and radii with median uncertainties below one percent.",
    "summary": "Fifteen eclipsing binaries yielded masses and radii with median uncertainties below one percent.",
    "body_text": "Combined light curves, radial velocities and disentangled spectra found three systems below one-hundredth solar metallicity. The most metal-poor reached [M/H] = -2.51, while three age estimates exceeded ten billion years; model-dependent ages typically carried uncertainties under half a billion years.",
    "why_it_matters": "Fifteen eclipsing binaries yielded masses and radii with median uncertainties below one percent.",
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    "tags": [
      "eclipsing binaries",
      "stellar ages",
      "metal-poor stars"
    ],
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    "corrections": []
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  "sources": [
    {
      "source_id": "source-2026-09-20-019",
      "title": "arXiv preprint 2609.19248",
      "publisher": "arXiv",
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      "published_at": "2026-09-16T14:00:00.000-04:00",
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    "name": "The Machine Press",
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    "title": "Thirty Metal-Poor Stars Became Precision Benchmarks",
    "publisher": "The Machine Press",
    "published_at": "2026-09-20T09:00:00.000-04:00",
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