AstroSky

Data and licences

AstroSky combines third-party forecast and catalogue data with calculations performed on your device. The sources below do not endorse AstroSky or its derived observing scores.

Forecast data

Based on data from MET Norway Locationforecast, licensed under CC BY 4.0 and NLOD 2.0 where applicable. AstroSky transforms source data into derived observing scores. MET Norway does not endorse AstroSky.

Satellite-light baseline

This product was made utilizing VIIRS Nighttime Light (VNL) data produced by the Earth Observation Group, Payne Institute for Public Policy, Colorado School of Mines.

Source: the EOG “For Artists” 2020 global composite, under CC BY-SA 4.0. AstroSky bundles the square-root visualisation and samples the area around a selected site locally to derive a qualitative artificial-light baseline. This processing is an AstroSky adaptation. It is not a live measurement, calibrated SQM reading or exact Bortle class.

Deep-sky target catalogue

The bundled 800-object catalogue is a selected and transformed subset of OpenNGC by Mattia Verga. The adapted catalogue remains under CC BY-SA 4.0, separate from the app’s code. AstroSky calculates target recommendations locally; Moon and planet positions are calculated with Astronomy Engine.

See the data-processing notes and bundled data and notices for the distributed assets and their provenance.

Open-source software