{
  "about": "Every source Besselian uses, with its citation, location, retrieval date and rights. Nothing is fetched from another host: the vendored files ship with the page, and the coastlines load from the same host the first time a path is drawn.",
  "sources": [
    {
      "id": "nasa-besselian",
      "citation": "F. Espenak, Besselian elements of the 224 solar eclipses 2001–2100, NASA Goddard Space Flight Center Eclipse Web Site",
      "url": "https://eclipse.gsfc.nasa.gov/SEbeselm/SEbeselm2001/SE2024Apr08Tbeselm.html (one page per eclipse; index: https://eclipse.gsfc.nasa.gov/SEdecade/SEdecade2001.html … SEdecade2091.html)",
      "retrieved": "2026-10-06",
      "vendored": "public/solar.json (by scripts/fetch-nasa.mjs, one request per second)",
      "rights": "US Government work, public domain. NASA's page: \"Permission is freely granted to reproduce this data when accompanied by an acknowledgment: Eclipse Predictions by Fred Espenak, NASA's GSFC\". The acknowledgment is printed on the page and in the README. No NASA logo is used."
    },
    {
      "id": "nasa-local-circumstances",
      "citation": "NASA GSFC Eclipse Web Site, interactive Google-map pages and their calculator SEcirc.js (X. Jubier and F. Espenak, 2007–2015)",
      "url": "https://eclipse.gsfc.nasa.gov/SEgoogle/SEgoogle2001/SE2024Apr08Tgoogle.html, SE2017Aug21Tgoogle.html, SE2026Aug12Tgoogle.html, SE2027Aug02Tgoogle.html; https://eclipse.gsfc.nasa.gov/SEgoogle/SEcirc.js",
      "retrieved": "2026-10-06",
      "vendored": "src/data/nasa-local.json (by scripts/nasa-receipts.mjs); raw pages in test/fixtures/nasa/",
      "rights": "US Government work, public domain, with the acknowledgment above. Used as receipts only."
    },
    {
      "id": "nasa-lunar",
      "citation": "F. Espenak, lunar eclipse decade tables 2001–2100 and lunar eclipse figures (2009 Apr 29), NASA GSFC Eclipse Web Site",
      "url": "https://eclipse.gsfc.nasa.gov/LEdecade/LEdecade2001.html … LEdecade2091.html; https://eclipse.gsfc.nasa.gov/LEplot/LEplot2001/LE2025Mar14T.pdf, LE2026Mar03T.pdf, LE2022Nov08T.pdf",
      "retrieved": "2026-10-06",
      "vendored": "test/fixtures/nasa-lunar-decades.json, test/fixtures/nasa-lunar-figures.json (receipts only; the page computes every lunar eclipse itself)",
      "rights": "US Government work, public domain, with the acknowledgment above."
    },
    {
      "id": "usno-deltat",
      "citation": "US Naval Observatory, observed ΔT (TT − UT1) by month, deltat.data",
      "url": "https://maia.usno.navy.mil/ser7/deltat.data",
      "retrieved": "2026-10-06",
      "vendored": "test/fixtures/usno-deltat.data (receipt only)",
      "rights": "US Government work, public domain."
    },
    {
      "id": "geonames",
      "citation": "GeoNames gazetteer, cities15000 dump (coordinates, elevation, IANA time zone of 92 cities)",
      "url": "https://download.geonames.org/export/dump/cities15000.zip",
      "retrieved": "2026-10-06",
      "vendored": "src/data/cities.json (by scripts/build-cities.mjs)",
      "rights": "Creative Commons Attribution 4.0 (CC BY 4.0), GeoNames, https://www.geonames.org/"
    },
    {
      "id": "almucantar",
      "citation": "Almucantar astronomy engine (Meeus Sun, Moon, time, nutation, obliquity, frames), N. Hagen, 2026-10-03",
      "url": "https://github.com/MeeshaBear1/almucantar (src/astro, commit 2c0bb11)",
      "retrieved": "2026-10-05",
      "vendored": "src/engine/astro/ (copied unchanged, credited in each file)",
      "rights": "MIT. Its lunar coefficient tables are transcribed from astronomia (MIT, S. Keys 2013, commenthol 2016), which transcribes Meeus Table 47.A and 47.B."
    },
    {
      "id": "methods",
      "citation": "Explanatory Supplement to the Astronomical Almanac, 3rd ed. (S. E. Urban and P. K. Seidelmann, eds., 2013), ch. 11; J. Meeus, Elements of Solar Eclipses 1951–2200 (Willmann-Bell, 1989); J. Meeus, Astronomical Algorithms, 2nd ed. (Willmann-Bell, 1998), ch. 25, 47, 54 and App. III; F. Espenak and J. Meeus, Five Millennium Canon of Solar Eclipses, NASA TP-2006-214141; F. Espenak and J. Meeus, Five Millennium Canon of Lunar Eclipses, NASA TP-2009-214172; W. Chauvenet, A Manual of Spherical and Practical Astronomy (1863)",
      "url": "",
      "retrieved": "",
      "vendored": "none: methods only, implemented in src/engine/",
      "rights": "Formulas are not copyrightable; no text from these works is reproduced."
    },
    {
      "id": "natural-earth-land",
      "citation": "Natural Earth, 1:110m physical vectors, land polygons (ne_110m_land), version as published in the nvkelso/natural-earth-vector repository",
      "url": "https://raw.githubusercontent.com/nvkelso/natural-earth-vector/master/geojson/ne_110m_land.geojson (project: https://www.naturalearthdata.com)",
      "retrieved": "2026-10-06",
      "vendored": "public/land.json (by scripts/build-land.mjs, rounded to 0.1 degree; one request)",
      "rights": "Public domain. Natural Earth: \"All versions of Natural Earth raster + vector map data found on this website are in the public domain.\" Credited on the page anyway."
    }
  ]
}