# Texture credits

## `2k_*` planet, Sun, ring & starfield maps — Solar System Scope (CC BY 4.0)

The **`2k_`** planet, Moon, Sun, ring and starfield maps in this directory are from
the **Solar System Scope** texture pack and are used under **CC BY 4.0**.

- Source: https://www.solarsystemscope.com/textures/
- License: Creative Commons Attribution 4.0 International (CC BY 4.0)
  https://creativecommons.org/licenses/by/4.0/
- Attribution: *Solar System Scope* (INOVE / solarsystemscope.com). Textures are
  based on NASA elevation and imagery data.

Downloaded 2026-07-16 at 2k resolution:

| File | Body |
|------|------|
| 2k_sun.jpg | Sun |
| 2k_mercury.jpg | Mercury |
| 2k_venus_surface.jpg | Venus (surface) |
| 2k_earth_daymap.jpg | Earth (day) |
| 2k_mars.jpg | Mars |
| 2k_jupiter.jpg | Jupiter |
| 2k_saturn.jpg | Saturn |
| 2k_uranus.jpg | Uranus |
| 2k_neptune.jpg | Neptune |
| 2k_moon.jpg | Moon |
| 2k_saturn_ring_alpha.png | Saturn rings (alpha) |
| 2k_stars_milky_way.jpg | Milky Way skybox panorama |

Attribution also appears in the app's HUD footer, as CC BY requires.

## `1k_*` moon maps — USGS Astrogeology / NASA (public domain)

Added wave 2 (PERIHELION · SELENE). Global equirectangular (simple-cylindrical)
mosaics from the **USGS Astrogeology Science Center** (`planetarymaps.usgs.gov`),
built from NASA mission imagery. USGS/NASA-produced planetary data are in the
**U.S. public domain** (no copyright asserted). Each was downloaded as a GeoTIFF
and downscaled to 1024×512 JPEG with `sips` (Europa re-encoded at q70 to stay
under budget). Downloaded 2026-07-16.

| File | Body | Mission / instrument | Source (USGS Astrogeology) | License |
|------|------|----------------------|----------------------------|---------|
| 1k_io.jpg | Io | Galileo SSI + Voyager, color-merge | `.../mosaic/Io_Galileo_SSI_Global_Mosaic_ClrMerge_1km.tif` | Public domain |
| 1k_europa.jpg | Europa | Voyager + Galileo SSI, global 500 m | `.../mosaic/Europa_Voyager_GalileoSSI_global_mosaic_500m.tif` | Public domain |
| 1k_ganymede.jpg | Ganymede | Voyager + Galileo SSI, global color 1435 m | `.../mosaic/Ganymede_Voyager_GalileoSSI_Global_ClrMosaic_1435m.tif` | Public domain |
| 1k_callisto.jpg | Callisto | Voyager + Galileo SSI, global 1 km | `.../mosaic/Callisto_Voyager_GalileoSSI_global_mosaic_1km.tif` | Public domain |
| 1k_titan.jpg | Titan | Cassini ISS, global mosaic (PIA19658), 4 km | `.../mosaic/Titan_ISS_P19658_Mosaic_Global_4km.tif` | Public domain |
| 1k_triton.jpg | Triton | Voyager 2, global color mosaic (gap-filled) 600 m | `.../mosaic/Triton_Voyager2_ClrMosaic_GlobalFill_600m.tif` | Public domain |
| 1k_charon.jpg | Charon | New Horizons LORRI/MVIC, global mosaic 300 m (Jul 2017) | `.../mosaic/Charon_NewHorizons_Global_Mosaic_300m_Jul2017_8bit.tif` | Public domain |
| 1k_phobos.jpg | Phobos | Mars Express HRSC-SRC, global mosaic 16 ppd | `.../mosaic/Phobos_ME_SRC_Mosaic_Global_16ppd.tif` | Public domain |

Host base URL: `https://planetarymaps.usgs.gov/mosaic/` (served from the USGS
`asc-pds-services` bucket). USGS terms: <https://www.usgs.gov/information-policies-and-instructions/copyrights-and-credits>.

**Directorial colourisation (PERIHELION closer).** USGS has no colour equirect for
Europa, Callisto, Titan, Phobos and Charon, so those mosaics ship grayscale. The
app multiplies each by its characteristic hue at render (`bodies.js` `tint`:
Titan orange, Europa/Charon tan, Callisto/Phobos warm-brown) — the *real surface
detail is preserved*; only the colour is an explicit directorial choice, not data.
Io, Ganymede and Triton are USGS colour mosaics and render untinted.

**Truth boundary (brief §7b):** these are the *real data* textures — real worlds
get real maps. The stylized grimoire portraits in `../art/grimoire/` are the
*aesthetic* layer (generated art), kept visually and directorially separate.