1. Tick ‘Auto-locate’ to update your location automatically during use (⁺ = current). (‘Locate once’ determines your current position once and stores it.) Nothing more is required for now. For higher accuracy enable ‘4. Agnihotra (GPS)’.
Alternatively, you may enter a place name or an address into the text field (if supported by your device) or coordinates (e.g. 50.94, 6.96). A 3rd and 4th entry are optional: approximate altitude [m], approximate temperature at twilight [°C]. Then enable the checkbox ‘Hide GPS notice’. You can save the entered coordinates as a favourite, for example with ‘.set Cabin’, recall them with ‘cabin’, or delete the favourite with ‘.del cabin’.
2. ‘Viewing direction’ defines whether the clock runs clockwise (south) or anticlockwise: when changing the direction of rotation, the part of the solar circle below the horizon is positioned in front of you (see page 3 for details). ‘Show digital clock’ displays a digital clock at the upper right of the dial. ‘night watches’ shows 4φ instead of 12ν temporal hours at night.
3. ‘Dark mode’ automatic mimics the sky’s twilight, -0° switches at sunset, -6° at the end of twilight. ‘Design’ selects different dials. ‘Extra margin’ increases the distance to the screen edge.
4. ‘Wall clock mode’ prevents the screen from turning off and switches to full screen. ‘Weather’ shows a forecast (internet required), from bottom to top: current temperature, day totals: precipitation, sunshine hours; see page 3 for symbols. ‘Agnihotra’ shows markers for the sun hand as well as the time of the next zero crossing of the Sun & countdown. Six minutes before Agnihotra, the display is enlarged and seconds are shown (⁺ = current GPS fix).
5. Alarms for sun times can be shifted using the minute fields and set with one click (Night limit = Sun at -12°). The alarms ring only once and must be reactivated daily because the sun times change.
You can zoom into the dial with two fingers (or with a double tap). If you want to move the zoomed image, do it slowly. Quick swipes take you to the next page. If your settings are not applied at some point, tap the ⟳ button at the bottom right. With the ⬌ button you activate ‘Time Control’ (see next page).
About
This software is a personal project. Please use it as it is. In principle, no personal data is collected or transmitted. No internet connection is required for operation. Details on optional features (weather display, place name resolution), error reports, and update checks can be found in the privacy policy.
This software is available in two versions: as a highly accurate Android app and as a lightweight web app for all devices, which can be used both with and without installation, starts quickly, and has a better time-travel mode.
If you have found an error, I will gladly correct it. I need a description of where and when the error occurred (possibly with a screenshot). A screenshot of the log below taken as soon as possible after the error occurred is also helpful (email contact: @).
Thanks to: Brandon Rhodes (Skyfield), Rolf, Greg Miller and all testers. Images: NASA/ SOHO, ESA/ Hubble, NASA/ JPL-Caltech (public domain). Weather data: Open-Meteo.com (CC BY 4.0), MET Norway (CC BY 4.0). Details: ‘design/ COPYRIGHT.txt’.
For ‘Time Control’ you can download additional ephemeris data here (and delete them again: ~17 MB, see page 3). – I provide ‘Sun Clock’ free of charge and hope you enjoy using it. If you would like to support my work, you can find my website here.
Explanation of the dial >
Gordon's Sun Clock Short info >
More information >
Support >
Automatic translation into more languages >