Privacy Policy for Astronomical Clock
Last update of this page: 2026-06-27
1. General
Gordon's Sun Clock Web is designed as a local browser-based web app / Progressive Web App (PWA). After the necessary files have been loaded, the core astronomical calculations are performed locally in the browser.
The web app does not require a user account. It does not use advertising trackers, social media trackers, analytics services, or profiling mechanisms.
Personal data are not collected, stored, or transmitted to the developer unless this is technically necessary for providing the website or for optional online features selected by the user. These cases are described below.
2. Website Access and Server Logs
When you open Gordon's Sun Clock Web in a browser, the browser requests the website files from the web server. For technical reasons, the web server or hosting provider may process access data such as:
- the requested file or URL,
- date and time of the request,
- IP address,
- browser and operating-system information transmitted by the browser,
- HTTP status code and transferred data volume,
- referrer information, if transmitted by the browser.
These data are processed for the technical delivery, security, and maintenance of the website. They are not used by the developer to create user profiles.
In addition, the web app may load a small technical maintenance pixel at /inc/m.php. It counts simple requests by day, week, month, year, and total count. No user profiles are created, and this counter does not permanently store details such as IP address, location, browser identifier, or referrer.
3. Local Browser Storage, Service Worker, and Offline Use
Gordon's Sun Clock Web uses local browser storage mechanisms in order to provide its app functions and offline capability. Depending on the browser, this may include local storage, IndexedDB, the browser cache, and the Service Worker cache.
The following data may be stored locally on your device:
- app settings,
- selected language,
- manually entered or selected location data,
- locally cached astronomical day and year data,
- locally cached web app files needed for offline use,
- locally cached resolved locations or elevation values, if such functions are used.
This local storage is used only to provide the requested app functions, improve performance, reduce repeated online requests, and enable offline use. The locally stored data remain on your device and are not synchronised with a developer server.
You can delete these data through your browser settings, for example by clearing website data, app data, cache, or storage for the website.
4. Browser Location Permission
Gordon's Sun Clock Web can use your location for the calculation of local astronomical data, such as sunrise, sunset, time-dependent sky positions, and related display values.
Browser-based location access is optional. It is used only after you grant permission in the browser. If you do not grant permission, you can use a manually entered location or a default location.
Location data are used locally in the browser for astronomical calculations. They are not sent to the developer. Location data may be transmitted only when you use optional online functions that require it, such as weather retrieval, elevation lookup, or place-name resolution, as described below.
5. Place-Name Resolution and Elevation Determination (Optional)
If you enter a place name or change a location, Gordon's Sun Clock Web may query external online services to resolve the place name into geographic coordinates or to determine the elevation above sea level.
Depending on the input, the following data may be transmitted to the respective external service:
- the place name you entered, for geocoding,
- or geographic coordinates, latitude and longitude, for elevation determination.
When the map view is opened, map tiles from OpenStreetMap may be loaded. In that case, the browser requests the required map tiles directly from the map server.
These requests are performed only on demand, for example when a location is entered or changed. They are not performed continuously in the background.
For elevation determination, the request may be made through the web app server endpoint /inc/p.php. In that case, the coordinates are transmitted to the web server and forwarded from there to OpenTopoData.
Services that may be used:
- OpenStreetMap / Nominatim for geocoding
- OpenTopoData for elevation determination
- OpenStreetMap map tiles for map display
Data processing by these services is subject to their respective privacy policies.
Resolved coordinates and elevation values may be stored locally in the browser to avoid repeated external requests. This cache is stored only on your device.
6. Weather Display (Optional)
Where the weather display is available and enabled, Gordon's Sun Clock Web may retrieve weather data from an external weather service.
If automatic location detection is enabled, an approximate location may be used for this purpose. The location coordinates are reduced to a coarse precision before transmission. Exact GPS coordinates are not required for the weather display. If automatic location detection is disabled, manually entered coordinates or a fixed default location may be used instead.
Supported weather services may include:
Data processing by these services is subject to their respective terms and privacy information.
7. Updates of the Web App
Gordon's Sun Clock Web may check for updated web app files when the website is opened or when the browser updates the Service Worker cache. For this purpose, the browser may request files such as the app manifest, Service Worker file, version file, JavaScript files, CSS files, fonts, images, or other app assets from the web server.
These requests are ordinary website requests. They do not require location data and are not used by the developer to create user profiles.
8. Crash and Error Reports
The web version of Gordon's Sun Clock does not currently transmit automatic crash or error reports to the developer.
Error messages may be visible locally in the browser's developer console.
If a future version introduces optional error reporting, this privacy policy will be updated before such reporting is used.
9. Browser Permissions
Depending on the features you choose to use, Gordon's Sun Clock Web may request the following browser permission:
- Location: optional, only after browser permission, used for local astronomical calculations and optional location-based features.
You can revoke browser permissions at any time in your browser or operating-system settings.
10. Legal Basis
The processing of website access data is necessary for providing the website, maintaining security, and ensuring technical operation.
Local browser storage is used where it is necessary to provide the requested app functions, remember settings, improve performance, and enable offline use.
Optional external requests, such as geocoding, elevation lookup, weather retrieval, or browser location access, are performed only when the respective function is used or enabled.
11. Recipients and Third-Party Services
Personal data are not sold and are not used for advertising profiles.
Data may be processed by the hosting provider as part of normal website delivery and server operation. Data may also be transmitted to the external services listed above when you use the respective optional functions.
12. Your Rights
Where applicable under data protection law, you may have the right to request information about personal data processed about you, and to request correction, deletion, restriction of processing, or objection to processing.
Because Gordon's Sun Clock Web does not use user accounts and stores most app data only locally in your browser, the developer may not be able to identify data stored on your device. You can delete locally stored data yourself through your browser settings.
You may also have the right to lodge a complaint with a competent data protection supervisory authority.
13. Developer
The developer of Gordon's Sun Clock Web is:
Gordon Axmann
Cologne, Germany
Gordon's Sun Clock Web is a free, private project.
14. Changes to This Privacy Policy
This privacy policy may be updated when necessary, for example when features, external services, storage behaviour, or legal requirements change. The version published on the website applies.