Web app

Web App PWA

Astronomical Sun Clock, usually shortened to Astronomical Clock, is the browser/PWA implementation of the Sun Clock. It runs directly in the browser, performs its astronomical calculations locally in JavaScript and can work offline after installation.

The PWA has nearly the same function set as Gordon's Sun Clock. It uses VSOP87 and IAU 2000B instead of Skyfield with JPL DE440 ephemerides, so it is considerably lighter and starts faster. It also allows live time travel through past and future dates. Sun-based alarms are still missing in the web implementation.

The PWA can be used directly at astronomicalclock.eu and can be installed on the Home Screen on phones and tablets.

iPhone / iPad

1. Open the web app in Safari.
2. Tap the Share button.
3. Select Add to Home Screen.
4. Tap Add.

Astronomical Sun Clock (AstrClck) will then appear on the Home Screen and can be opened like a normal app.

Android

1. Open the web app in Chrome or Firefox.
2. Open the browser menu.
3. Select Add to Home screen or Install app, depending on the browser. In Firefox, use More / Add to Home screen.
4. Confirm.

Astronomical Sun Clock (AstrClck) will then be available from the Home Screen or app launcher.

There is also a separate Android package of Astronomical Clock; see Download. The original Android/Python implementation is Gordon's Sun Clock.

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