Siderial time, yearly calendar marker, counter-rotating star wheel, bezel-compass, 24h marker and astronomical navigation. 4 star-wheels included with two different styles covering both northern and southern hemispheres (north installed). Yellow hand shows local right ascension on yellow number circle, yellow triangle indicates battery level. Star wheel may require initial adjustment for your home longitude. In editor, the last rotation value is the angular offset. This is not critical though, it only matters for active astronomers, navigation does not rely on this adjustment. Looks very cool as wallpaper. Never get lost in space again! For pilots, hikers, skippers, migrating birds and vampires.