# Preview source and licence notices

Astronomy Engine 2.1.19, copyright Don Cross, MIT. The complete MIT notice is preserved at the head of `vendor/astronomy-engine-2.1.19.mjs`. Upstream: https://github.com/cosinekitty/astronomy

Star catalogue: David Nash / Astronexus, AT-HYG v3.2, combining HYG 4.1 and Tycho-2, CC BY-SA 4.0. Adapted from the previously audited September Book Sky Chart Generator subset. This preview selects 8,893 stars of magnitude <=6.5 plus two additional matched figure endpoints. Rows with missing proper motion are excluded (one otherwise eligible magnitude <=6.5 row). Positions and proper motion values are preserved, and no completeness is claimed. The adapted `data/catalogue.json` star data is distributed under CC BY-SA 4.0, including attribution and the permission to redistribute/adapt under that licence. Source and adaptation hashes are in `data/manifest.json`. https://github.com/astronexus/ATHYG-Database and https://creativecommons.org/licenses/by-sa/4.0/

Constellation figures: Olaf Frohn, d3-celestial, BSD 3-Clause; see `d3-celestial-LICENSE.txt`. Figure coordinates were matched to catalogue IDs within 0.03 degrees to apply the same epoch transformation as their stars. These are one illustrative connecting-line convention, not official IAU constellation boundaries. https://github.com/ofrohn/d3-celestial

Atkinson Hyperlegible: Braille Institute, SIL Open Font License 1.1, see `Atkinson-OFL.txt`. Font included unchanged.

No Stellarium source code, textures or catalogues are incorporated. Stellarium is intended only as an independent validation tool.

Commercial use is permitted by these licences, subject to their conditions. The star data adaptation has share-alike obligations. Licensing of customer chart derivatives must be resolved explicitly before commercial release; payment must not imply exclusive ownership of underlying catalogue data.

The new application code is a private development prototype. These data licences do not automatically relicense separate application code.

Cormorant Garamond: copyright the Cormorant Project Authors, SIL Open Font License 1.1; see Cormorant-OFL.txt. Unmodified source https://github.com/google/fonts/tree/main/ofl/cormorantgaramond . SHA-256 b20b7d9626dd956b2c5e558692ad328b1f19e3275e2782db4fa07670d83f35e0.

Places: GeoNames, Creative Commons Attribution 4.0. Derived from cities500 plus Australian populated places, filtering feature types and retaining names/aliases, approximate centres and IANA zones; Australian state labels abbreviated. https://www.geonames.org/ and https://creativecommons.org/licenses/by/4.0/ . Original readme is included as GeoNames-README.txt; provenance and input/output hashes are in data/world-places-manifest.json. Provided without completeness/accuracy warranty.