# Earth scene assets

Earth day, night and packed bump/roughness/cloud maps: Solar System Scope / INOVE, https://www.solarsystemscope.com/textures/ . Licensed under Creative Commons Attribution 4.0 International: https://creativecommons.org/licenses/by/4.0/ .

This copy uses the resized and merged maps distributed in the official Three.js examples: https://github.com/mrdoob/three.js/tree/dev/examples/textures/planets . Shader color grading, lighting and cloud motion are modifications for this website. These are artwork, not live satellite or meteorological observations.

Three.js is reused from this project's existing /airport-sandbox/vendor/ directory. Its MIT license is retained there as LICENSE.three.

Moon surface texture: Three.js examples, https://github.com/mrdoob/three.js/blob/dev/examples/textures/planets/moon_1024.jpg . Star field and distant dust band are procedurally generated. Composition is artistic, not a scale model.

Astronomical calculations: Astronomy Engine 2.1.19 by Don Cross, MIT (license included in astronomy.js). https://github.com/cosinekitty/astronomy
Earth texture mapping: Greenwich = +X, north = +Y, east = -Z. Sun/Moon EQJ vectors are rotated to equator-of-date, then Earth-fixed using Greenwich apparent sidereal time. Sun direction is rotated with the viewing transform, not held fixed while geography is dragged.
Solar-system longitudes/latitudes are computed from heliocentric ecliptic-of-date vectors. Display radius = 2.2 ln(1 + distance in AU). Planet sizes are independently enlarged; circular guide lines are not osculating orbits. The asteroid belt is a schematic annulus at 2.1–3.3 AU, not tracked individual asteroids. Background stars are decorative, not a star catalogue.
Saturn surface: Solar System Scope, CC BY 4.0, https://www.solarsystemscope.com/textures/ . Jupiter cloud bands are procedural illustration, not live imagery.
Space-station models are procedural simplified ISS / Tiangong basic T configuration. Ideal circular demonstration orbits near 400 km, with nominal inclinations 51.6 / 41.5 degrees. Initial orbital phases and nodes are illustrative; no TLE/live telemetry is claimed. Model sizes and motion are exaggerated.
References: https://www.nasa.gov/reference/international-space-station/ ; https://en.cmse.gov.cn/missions/mengtian/ ; https://science.nasa.gov/solar-system/asteroids/facts/

## Unified scene (v12)
All bodies coexist in one Earth-fixed scene. OrbitControls moves the camera, not the globe or sunlight. Geocentric planet directions are computed from UTC. Planet display distance = 12 + 25 ln(1 + 8 distanceAU), in Earth-radius scene units. Moon distance is compressed 5:1. The asteroid annulus is transformed from heliocentric ecliptic coordinates to the Earth-fixed view. Sizes are illustrative. This supersedes the earlier separate solar-view description above.

ISS: NASA 3D Resources, International Space Station (ISS) (D) (IGOAL), NASA / JSC / IGOAL.
Source: https://github.com/nasa/NASA-3D-Resources/tree/master/3D%20Models/International%20Space%20Station%20(ISS)%20(D)%20(IGOAL)
Usage guidance: https://www.nasa.gov/nasa-brand-center/images-and-media/
Modified for web delivery: mesh simplification, Draco compression and resized WebP textures. Original relative geometry proportions retained, uniformly enlarged relative to Earth for visibility. No endorsement implied.
Tiangong remains a procedural reconstruction of the basic T configuration, not an official model. Both station orbits now use a nominal 93-minute period; phases/nodes are illustrative, not live tracking. This supersedes the earlier simplified-ISS and accelerated-motion description.
Three.js r186 addons (OrbitControls, GLTFLoader, DRACOLoader, BufferGeometryUtils, SkeletonUtils) are from https://github.com/mrdoob/three.js under MIT, license at /airport-sandbox/vendor/LICENSE.three. Draco decoder from Three.js examples, Google Draco Apache-2.0: https://github.com/google/draco/blob/main/LICENSE .

## v13 rendering and imagery
Earth day: NASA Blue Marble monthly October map, public domain, via https://github.com/matteason/live-cloud-maps/tree/main/static_images/monthly . Ocean mask from the same repository. Earth and independent cloud shell rotate in an epoch-oriented scene; 120x Earth rotation is an explicitly labeled visual demonstration. 1x selects the real sidereal rotation rate. Relative cloud drift in demonstration mode is artistic, not measured winds or weather forecasting. Near-real-time satellite cloud snapshots update separately.
Cloud imagery: Contains modified EUMETSAT data. Processed by Matt Eason's Live Cloud Maps, https://github.com/matteason/live-cloud-maps (CC0 images/code, EUMETSAT attribution retained). Provider updates nominally every three hours. The website displays fetch time because the upstream response does not supply an observation timestamp; freshness is not guaranteed. Polar gaps are filled by the source. Local fallback retrieved 2026-10-09. Endpoint is cached for 30 minutes; unavailable refreshes retain the prior snapshot with a visible notice.
Planet, Moon, Sun, Saturn ring and Milky Way textures: Solar System Scope / INOVE https://ssi.solarsystemscope.com/textures/ under CC BY 4.0 https://creativecommons.org/licenses/by/4.0/ . Based on imagery with artistic adjustments and gap filling, not live planetary images. Converted/resized to WebP. Jupiter obtained via https://commons.wikimedia.org/wiki/File:Solarsystemscope_texture_8k_jupiter.jpg ; Uranus via the unmodified Solar System Scope asset mirrored in https://github.com/TanvirAhmedArnab/SolarSystem . Other maps from the publisher's download links. v13 replaces the former hand-drawn Jupiter stripes and procedural star backdrop. Planet rotation is illustrative; distances/sizes are compressed for navigation and are not to scale.