# Credits & licences — surpasscomputing.com preview

All third-party data below is used unmodified in content and only resized, re-projected, channel-packed
or re-encoded (JPEG) by `tools/build_assets.py`. Originals are not committed; the script documents every step.

## Earth
| Asset (public/assets/earth/…) | Source | Licence / credit |
|---|---|---|
| `day_hi/lo.jpg` — global surface colour | NASA Blue Marble: Next Generation, Topography & Bathymetry, Dec 2004, 21600×10800 (`world.topo.bathy.200412.3x21600x10800.jpg`) — https://eoimages.gsfc.nasa.gov/images/imagerecords/73000/73909/ | Public domain (NASA). Credit: NASA Earth Observatory / Reto Stöckli (NASA GSFC) |
| `patch_hi/lo.jpg` — hero region 2°–42° N, 94°–50° W (Caribbean, Gulf, Florida, Central America) | NOAA-20 VIIRS Corrected Reflectance (True Color), 2024-03-12, via NASA GIBS WMS (`VIIRS_NOAA20_CorrectedReflectance_TrueColor`), stitched from 16 tiles at 6144 px | No restrictions on use (NASA EOSDIS data policy). "We acknowledge the use of imagery from the NASA Worldview application (https://worldview.earthdata.nasa.gov), part of the NASA Earth Science Data and Information System (ESDIS)." |
| `aux2_*.jpg` R channel — global clouds (sparse, high-pass detail; `tools/build_aux.py`) | NASA Visible Earth, Blue Marble clouds `cloud_combined_8192.tif` — https://eoimages.gsfc.nasa.gov/images/imagerecords/57000/57747/ | Public domain (NASA Goddard Space Flight Center / MODIS) |
| `aux2_*.jpg` (2k / 4k / 8k, 4:4:4), `patchaux_*.jpg` G channel — night lights (unsharp-masked) | NASA Black Marble 2016 (VIIRS DNB) `BlackMarble_2016_3km.jpg` — https://eoimages.gsfc.nasa.gov/images/imagerecords/144000/144898/ | Public domain. Credit: NASA Earth Observatory (Joshua Stevens, Miguel Román, NASA GSFC) |
| `aux2_*.jpg` B channel — ocean/water specular mask, `normal.jpg`, `patchnormal_*.jpg` — relief normals | GEBCO_08 elevation via NASA Visible Earth `gebco_08_rev_elev_21600x10800.png` — https://eoimages.gsfc.nasa.gov/images/imagerecords/73000/73934/ (mask combined with Blue Marble colour) | GEBCO grid: free to use with attribution ("GEBCO Compilation Group, GEBCO_08 Grid"); Visible Earth rendition: NASA, public domain |
| `patchaux_*.jpg` R channel | Cloud mask derived from the VIIRS patch above | as above |

## Live data (fetched at runtime through the Worker's `/api/*` proxy)
| Data | Source | Licence / credit / limits |
|---|---|---|
| ISS orbit — current two-line element set (NORAD 25544), propagated with SGP4 in the browser | CelesTrak GP data, `https://celestrak.org/NORAD/elements/gp.php?CATNR=25544&FORMAT=TLE` (proxied as `/api/tle`, edge-cached 6 h; bundled fallback TLE in `src/worker.js` and `public/js/orbit.js`) | Orbital data courtesy of **CelesTrak (Dr T.S. Kelso)**, derived from US Space Force / 18 SDS (space-track.org) public GP data. CelesTrak asks clients not to re-download unchanged GP data more than about once per 2 h; the 6 h edge cache keeps the preview far below that. |
| Near-real-time Earth imagery around the sub-satellite point — LIVE EARTH toggle (off by default; offered only on devices that hold the top quality tier; `?liveweather` forces it on) | NASA GIBS WMTS, EPSG:4326 `250m` tile set, layer `VIIRS_NOAA20_CorrectedReflectance_TrueColor` (SNPP / MODIS Terra selectable with `?layer=`), yesterday's UTC date (or the `?t=` date if older), zoom 5 (desktop, 6×4 tiles) / 4 (phones, 4×3) — proxied as `/api/gibs/<layer>/<date>/<z>/<row>/<col>.jpg`, edge-cached 3 h (recent) / 30 days (older) | NASA EOSDIS data: no restrictions on use. "We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS)." GIBS has no API key and no published hard rate limit; the proxy only serves a fixed whitelist of layers/levels and caches every tile. |
| Sun position | `sunPos` from satellite.js (Vallado algorithm) for the current UTC | — |
| Moon position (topocentric from the ISS) and phase | Meeus, *Astronomical Algorithms* ch. 47 (main periodic terms, ~0.3°), implemented in `public/js/orbit.js` | — |
| `assets/earth/landmask.bin` ("over:" readout) | 1° land/water mask downsampled from the Blue Marble/GEBCO water mask above; region names are coarse hand-written lat/lon boxes (approximate) | as above |

## Sky
| Asset | Source | Licence / credit |
|---|---|---|
| `sky/starmap_hi.jpg` (8192×4096), `starmap_lo.jpg` (4096×2048) — all-sky Milky Way | NASA SVS *Deep Star Maps 2020* (ID 4851, Ernie Wright), `starmap_2020_8k.exr`, celestial (RA/Dec) projection — https://svs.gsfc.nasa.gov/4851 | Credit: **NASA/Goddard Space Flight Center Scientific Visualization Studio. Gaia DR2: ESA/Gaia/DPAC.** Built from Hipparcos-2, Tycho-2, Gaia DR2 (1.7 billion stars) with the Yale BSC, UCAC3 and XHIP. Note: ESA licenses Gaia data products under CC BY-SA 3.0 IGO; the resized map is offered under the same terms. |
| `sky/bsc5.json` — 9,096 bright stars (RA, Dec, V mag, Teff) for sharp point stars | Yale Bright Star Catalogue, 5th revised ed. (Hoffleit & Warren 1991, NASA ADC / Harvard TDC) via https://github.com/brettonw/YaleBrightStarCatalog (`bsc5-short.json`) | Catalogue: public scientific data (NASA ADC). JSON conversion © 2016 Bretton Wade, MIT licence |

## Moon
| Asset | Source | Licence / credit |
|---|---|---|
| `moon/color_hi/lo.jpg` | NASA SVS *CGI Moon Kit* (ID 4720), LRO LROC WAC colour mosaic `lroc_color_poles_4k.tif` — https://svs.gsfc.nasa.gov/4720 | Public domain. Credit: NASA's Scientific Visualization Studio; LRO LROC (NASA/GSFC/Arizona State University) |
| `moon/normal.jpg` | Same kit, LOLA displacement `ldem_4.tif` (km, 4 px/deg) → tangent-space normals | Public domain. Credit: NASA SVS; LRO LOLA (NASA/GSFC) |

## Cockpit materials (CC0)
All from ambientCG (https://ambientcg.com), licensed **CC0 1.0** (no attribution required, credited anyway).
Colour (some desaturated), NormalGL, and packed ARM (AO/Roughness/Metalness) maps resized to 1024².

| Asset (public/assets/pbr/…) | ambientCG set |
|---|---|
| `plates_*` | MetalPlates006 |
| `painted_*` | PaintedMetal004 |
| `gunmetal_*` | Metal038 |
| `fabric_*` | Fabric061 |
| `leather_*` | Leather030 |
| `rubber_*` | Rubber004 |
| `weave_normal.jpg` | not ambientCG: procedural 2/2 twill normal map generated by `tools/make_weave.py` (original work) |

## Code
- three.js r169 (vendored under `public/vendor/three/`), MIT licence © 2010-2024 three.js authors — including the GTAO, bloom, output and shader passes from `examples/jsm`.
- satellite.js 7.1.0 (vendored JS build under `public/vendor/satellite/`, WASM bulk propagator omitted), MIT licence © 2013 Shashwat Kandadai and UCSC; SGP4 after Vallado et al. (2006).
- Atmosphere: single-scattering Rayleigh/Mie/ozone model written for this project; coefficients from Bruneton & Neyret, *Precomputed Atmospheric Scattering* (2008) / Hillaire (2020).
- Everything else (cockpit, pilot, holograms, warp, shaders, attitude control, the blue nebula haze and hero-star diffraction spikes, which are artistic additions and not catalogue data) is original work for Surpass Computing.

## Evaluated, not used
- Third-party cockpit / glove / hand / pilot models (Oct 2026 search): Sketchfab downloadable CC-BY/CC0 (e.g. "Spacefighter Cockpit (Wasp Interdictor)" db4aa67, "Sci-fi Spaceship Cockpit 02" c682589, "A Sci-Fi Cockpit Concept" 4a16f37, "First Person arms" e3c42c0, "Sci-Fi Pilot Seat" 5277044), Poly Haven, Kenney Space Kit (CC0), Quaternius Modular Sci-Fi MegaKit (CC0), NASA 3D Resources and Smithsonian 3D (Apollo 11 CM interior scan, CC0). None was clearly better than the procedural build for this framing (dated/stylized/low-poly, central joystick layouts, bare or fingerless hands, scan-heavy, or third-party IP), so **no third-party model is used**. Note: Sketchfab file downloads require a signed-in account, so Sketchfab candidates were judged from Sketchfab's own renders (shots/model-candidates-free.png), not from local headless renders of the files.
- The cockpit interior (central console tower, side consoles, struts, gloves, sleeves, legs) is procedurally modelled in `public/js/interior.js`, `pilot-arms.js`, `pilot-legs.js`; all screen content is generated at runtime on canvas.
- KTX2/Basis texture compression: no encoder available in the build environment; resized progressive JPEGs with mipmaps used instead.