# Third-party notices

This app bundles the third-party work listed below. Every item is public domain or under an open licence.

| Component | Where | Licence |
| --- | --- | --- |
| IGRF-14 Gauss coefficients, IAGA Working Group V-MOD | `data/igrf14.json`, rearranged from NOAA NCEI's `igrf14coeffs.txt`; values unchanged | CC BY 4.0 |
| Natural Earth 1:110m coastlines, simplified | `data/coast-110m.json`, the front page's copy | Public domain |
| Natural Earth 1:10m populated places, with IANA time zones | `data/cities.json`, the Daylight Atlas's copy | Public domain |
| Go fonts (Regular, Italic, Smallcaps, Mono) by Bigelow & Holmes | `fonts/`, WOFF2 subsets | BSD-3-Clause style (`fonts/LICENSE`) |

Nothing is loaded from a CDN, a font service or any other site, and the app makes no network requests beyond its own files.

## IGRF-14

International Geomagnetic Reference Field, fourteenth generation. C. D. Beggan et al., "International geomagnetic reference field: the fourteenth generation", *Earth, Planets and Space* 78, 127 (2026), doi:10.1186/s40623-025-02360-0, published under the Creative Commons Attribution 4.0 licence (https://creativecommons.org/licenses/by/4.0/). Coefficients as distributed by NOAA NCEI at https://www.ngdc.noaa.gov/IAGA/vmod/igrf.html. The page computes the field from them; it does not change them.

## Natural Earth

Made with Natural Earth. Free vector and raster map data at [naturalearthdata.com](https://www.naturalearthdata.com/). Natural Earth data is in the public domain; no permission is needed to use it.