Where the files in this folder come from (the Almanac's Earth view, almanac-earth.js).

earth-day-v1.webp
  NASA Earth Observatory, Blue Marble: Next Generation, July 2004, topography
  (world.topo.200407.3x5400x2700.jpg), Reto Stockli, NASA Goddard Space Flight
  Center. Public domain (NASA imagery). Resized to 2048x1024, WebP quality 75.
  https://science.nasa.gov/earth/earth-observatory/blue-marble-next-generation/

earth-night-v1.webp
  NASA Earth Observatory, Black Marble 2016 (BlackMarble_2016_01deg.jpg),
  Joshua Stevens / Miguel Roman, NASA. Public domain. Greyscale, 2048x1024,
  WebP quality 75.
  https://earthobservatory.nasa.gov/features/NightLights

moon-v1.webp
  NASA Scientific Visualization Studio, CGI Moon Kit (lroc_color_poles_1k.jpg),
  from the Lunar Reconnaissance Orbiter Camera. Public domain. Greyscale,
  1024x512, WebP quality 75. Also the map every 2D Moon is drawn from (the
  Almanac hero, the Today card, the sky scene; app.js _MOON_MAP_URL).
  https://svs.gsfc.nasa.gov/4720

moon-4k-v1.webp
  NASA Scientific Visualization Studio, CGI Moon Kit (lroc_color_poles_4k.tif),
  from the Lunar Reconnaissance Orbiter Camera's Wide Angle Camera mosaic.
  Public domain. Greyscale, 4096x2048, WebP quality 75 (cwebp 1.6.0). Fetched
  after the first paint and drawn wherever a Moon is wide enough to show it
  (the hero, the 3D view; app.js _MOON_MAP_HI_URL). Credited with the other
  NASA images in the 3D view ("Images: NASA").
  https://svs.gsfc.nasa.gov/4720

three-r186.min.js (three-LICENSE.txt)
  three.js r186, MIT License. Tree-shaken and minified; the build line is in
  the file's first comment.

satellite-7.1.0.min.js (satellite.js-LICENSE.txt)
  satellite.js 7.1.0, MIT License: SGP4/SDP4 only. The build line is in the
  file's first comment.

stars-v1.bin
  Yale Bright Star Catalogue, 5th revised edition (BSC5), Hoffleit and Warren,
  1991 (Astronomical Data Center catalogue V/50). Public domain. 9,096 stars to
  visual magnitude 7.96 with a J2000 position: right ascension and declination,
  V magnitude and B-V, packed to 6 bytes a star (54,580 bytes) by
  scripts/build_star_catalog.py, which documents the format. Drawn as the 3D
  view's star sphere (almanac-earth.js _aeStarField), fetched the first time
  that view opens.
  http://tdc-www.harvard.edu/catalogs/bsc5.html

milkyway-v1.webp
  ESO / S. Brunier, "The Milky Way panorama" (eso0932a), a photographic
  all-sky mosaic in galactic coordinates. CC BY 4.0: credit ESO/S. Brunier,
  https://www.eso.org/public/images/eso0932a/ . Changed by Zimi: the point
  stars removed (a grey opening over a 5 px window, so the dust lanes stay and
  the catalogue stars in stars-v1.bin are not drawn twice), a faint noise
  floor subtracted, resized to 2048x1024, WebP quality 90. Longitude runs to
  the left from the centre (l = 0 in the middle), latitude +90 at the top;
  almanac-skygl.js _sgGalUV is that map. Drawn behind the stars of the live
  sky (almanac-sky.js). Credited in THIRD_PARTY_NOTICES.md.

constellations-v1.json
  The 88 IAU constellations' figures and label places, packed by
  scripts/build_constellations.py from d3-celestial's constellations.lines.json
  and constellations.json (Olaf Frohn, BSD 3-Clause, github.com/ofrohn/d3-celestial;
  the lines follow the IAU's constellation pages with the author's
  modifications). Licence text: d3-celestial-LICENSE.txt. Stellarium's
  constellation data is GPL and is not used.
  Drawn by the live sky (almanac-sky.js _skyPaintConstellations), 15 KB.

Moon and Earth: the Earth view's maps above (moon-v1.webp, earth-day-v1.webp,
earth-night-v1.webp). Saturn's rings are drawn from their measured radial
structure (Cassini Division 117,500-122,200 km, Encke Gap near 133,500 km).
