Astrospheric is a very powerful website and mobile app that forecasts sky conditions as they relate to astronomical observing. The full website has many more features, like an “Astronomical Clock”, that shows when certain celestial objects will be above/below the horizon, an “Aurora Nowcast”, that shows predicted geomagnetic conditions, and an ISS Flyover tracker that shows when the International Space Station will be visible overhead in a selected location. Check out the widget below to see some of the features available for free.
