# Sources and licenses

MoonMap source is MIT. Keep `dist/THIRD_PARTY_LICENSES.txt` when distributing the built library; it includes Three.js (MIT), OpenLayers (BSD-2-Clause), proj4 (MIT), and their installed production dependencies. The examples' translated Chinese labels are editorial display names, not an additional official naming catalog.

## 3D imagery and terrain (default)

- [NASA Scientific Visualization Studio, CGI Moon Kit](https://svs.gsfc.nasa.gov/4720/), retrieved 2026-09-16.
- 2025 LROC color product: `lroc_color_16bit_srgb_4k.tif`, converted to 4096 × 2048 WebP.
- LOLA elevation: `ldem_4_uint.tif` for displaced geometry; `ldem_16_uint.tif` for a physical-slope tangent normal map.
- Source TIFF directory: [NASA SVS original files](https://svs.gsfc.nasa.gov/vis/a000000/a004700/a004720/).
- Height encoding: uint16 × 0.5 − 10000 metres relative to the 1,737.4 km reference sphere.
- Attribution: NASA's Scientific Visualization Studio / LROC / LOLA. Keep attribution when redistributing derived textures.
- [NASA media usage guidance](https://www.nasa.gov/nasa-brand-center/images-and-media/). These resources do not imply NASA endorsement. The project MIT license does not replace source media terms or authorize use of NASA insignia.
- Color is intended for visualization, not scientific quantitative reflectance analysis. No claim of live sunlight, navigation accuracy or metre-scale terrain is made.
- `assets/sources.json` contains dimensions, transformations and source / output SHA-256 checksums.
- The bundled default assets are served by the host application. They do not send user business features to NASA or require live NASA service availability.

## 2D imagery (optional entry)

- [NASA Moon Trek WMTS services](https://trek.nasa.gov/tiles/apidoc/trekAPI.html?body=moon).
- Global: `LRO_WAC_Mosaic_Global_303ppd_v02`, 303 pixels/degree.
- North: `LRO_WAC_Mosaic_NPole60_100m_v02`.
- South: `LRO_WAC_Mosaic_SPole60_100m_v02`.
- Attribution: NASA / GSFC / ASU / LROC / Moon Trek.
- [USGS source dataset and metadata](https://astrogeology.usgs.gov/search/map/moon_lro_lroc_wac_global_morphology_mosaic_100m): public-domain imagery, with author citation requested. The WAC morphology mosaic combines observations acquired at different times; it is not a real-time lighting or surface-condition product.

Default grids are a snapshot of the services' WMTS capabilities inspected on 2026-09-16. Polar capabilities use the placeholder `EPSG::0`; the corresponding Moon Trek catalog identifies Moon polar stereographic, radius 1,737,400 m, central meridian 0°, scale at the pole 1. The built-in adapters bind these known products to explicit lunar projections. Global resolutions derive from the 2:1 angular grid, not Earth-based WMTS scale denominators.

WAC source imagery is nominally 100 m/pixel. These public tile pyramids currently end at approximately 83 m/pixel at the global equator and 268 projected m/pixel in the polar service. Zooming beyond those levels enlarges existing imagery; it does not add ground detail. Sampling resolution is not positional accuracy.

## Names

- [IAU Gazetteer of Planetary Nomenclature, maintained by USGS](https://planetarynames.wr.usgs.gov/GIS_Downloads).
- [Official Moon KML download](https://asc-planetarynames-data.s3.us-west-2.amazonaws.com/MOON_nomenclature_center_pts.kmz), retrieved 2026-09-16; archive timestamp 2026-09-15, LOLA 2011 control network.
- The demo includes 22 selected feature-center coordinates and a source link for each. Feature centers are not crater outlines, landing locations or navigation waypoints.
- To regenerate: download the official KMZ and run `python scripts/extract-landmarks.py /path/to/MOON_nomenclature_center_pts.kmz` from the project root. The script rejects missing expected names.

Public services do not provide a service-level guarantee to MoonMap. Deployments may substitute their own same-projection WMTS and must retain the appropriate attribution. MoonMap does not upload business feature data; the imagery provider receives normal tile requests revealing the requested map area.