Hi,
Could you create a layer that shows the conditions for stargazing - i.e. taking into account light pollution and visibility. This would need to combine:
- sunrise/sunset
- moonrise/moonset/moon phase
- fixed light pollution from human sources (see https://www.lightpollutionmap.info )
- cloud cover
- fog
- aurora forecast (ideally it would be good to be able to see the layer with/without this included, as you may want to observe the aurora)
Algorithms for sun/moon are at: https://github.com/mourner/suncalc
Light pollution: https://www.lightpollutionmap.info/help.html
Space weather / Aurora: https://www.swpc.noaa.gov/