Data sources

The weather data we use comes from Open-Meteo, under a CC BY 4.0 license. City names, coordinates, elevation and population come from GeoNames, also under CC BY 4.0, and the coastline from Natural Earth, in the public domain. Sunrise and sunset times are calculated with standard astronomical methods.

When you search for a place that has no page of its own, such as a town, a neighborhood or a park, we look it up in Open-Meteo's place search, with GeoNames data, and in Photon, by Komoot, with data © OpenStreetMap contributors under the ODbL license.

The way we combine this data to estimate sky quality is our own.

Sun and shade map

The map's streets and buildings, with their heights, come from OpenStreetMap, with data © OpenStreetMap contributors under the ODbL license, served as OpenMapTiles tiles through OpenFreeMap. Terrain elevation comes from Terrain Tiles, published in the AWS Registry of Open Data, and the cloud imagery from NASA's GIBS service, in the public domain. The sun's position and the length of every shadow are calculated right here, minute by minute.

If a browser cannot show the map in 3D, a flat map with the standard OpenStreetMap tiles is shown instead, also with data © OpenStreetMap contributors under the ODbL license.

Photographs

The site's photographs are by these photographers, published on Pexels and Unsplash under free-to-use licenses. We never present them as community photos: the community gallery only shows photos uploaded by their own authors, and when a card uses one of these photos as an illustration, it says so.