Astronomical clock settings
Astronomical Clock (Sun, Moon, Sunrise, Sunset)
Live local time for the selected time zone, with sunrise and sunset plus a moon phase readout. Fullscreen supported.
Location storage and privacy
This route stores the selected latitude, longitude, and IANA time zone in the localStorage entry named astroClockPrefs. The values stay there until you press Clear location or clear this site's browser data. They are saved so the same location can be restored after a refresh.
The sun and moon calculations on this route run in the page. The route does not send the coordinates to an astronomy service, include them in the URL, or add them to structured data. Press Clear location to remove the saved latitude and longitude. The time zone remains as a display preference. Unavailable, denied, malformed, and out-of-range location data is ignored.
The iLoveTimers browser storage guide places this location preference in the full production inventory and explains how browser site-data clearing affects it.
Solar and lunar calculation method
Sunrise and sunset use a compact NOAA-style solar approximation with a 90.833 degree zenith. Inputs are the selected local calendar date, latitude, and longitude. The chosen time zone controls that calendar date and formats the calculated UTC event instants. The sun-altitude label uses a simpler day-of-year, declination, and equation-of-time estimate. Results are calculated locally, not retrieved.
The moon display uses a mean synodic month of 29.530588853 days from a reference new moon at 2000-01-06 18:14 UTC. Illumination is estimated with a cosine phase model and rounded to a whole percent. It does not calculate moonrise, moonset, libration, or the observer's apparent lunar position.
Example: choose the New York preset. The page uses latitude 40.7128, longitude -74.0060, the local date in America/New_York, then formats each calculated UTC instant in that zone. Clear location removes those coordinates from storage.
These estimates are intended for general display near the present date. Atmospheric refraction, elevation, terrain, weather, and the visible horizon are not modeled. Do not use them for observation planning that needs an almanac, navigation, or safety-critical decisions.
Sources: NOAA solar calculation details; U.S. Naval Observatory moon phase data; IANA Time Zone Database.
Combine the saved location with device time
Choose a listed city or use device location. The selected latitude, longitude, and IANA time zone drive the local solar and lunar estimates. Clear location removes the saved location values from this browser.
Selecting New York loads its location and zone, then shows calculated solar events and the modeled moon state for the current date. Choosing London changes both the coordinates and the civil-time basis. These are disclosed approximations rather than broad observational validation.