If you own an Android device (smartphone or tablet) you may want to take advantage of the new app "Sol Et Umbra" that means "Sun and Shadow". It is available for free from the usual Google app market.
Sol Et Umbra is basically an app that shows sun ephemeris for the actual (or whichever desired) time and date: - latitude and longitude - right ascension and declination - local azimuth and height - equation of time - local or time zone sun time - local or time zone mean time - time of rise, set and transit (local noon) - total number of hours of light Moreover Sol Et Umbra shows the time using italic, babilonic and temporal time systems. It also shows the time of Muslims prayers (that are strictly related to the position of the sun): Fajr, Zuhr, Asr1, Asr2, Maghrib and Isha. Sol Et Umbra can use the orientation sensors available in the device in order to compute and show the time lines of a sundial designed on the plane of the display. The graph is updated after any movement of the device. Finally the app can show the lighting conditions of a dial that is drawn on the device plane by means of an azimut / height graph that shows for any day in the year and for any hour in the day when the dial is lighted. More information on the program are available from my site: http://digilander. libero.it/orologi.solari/download/SolEtUmbraENU.html Ciao. Gian --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
