lunatic.watch

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A 24-hour clock that follows the sun.

• One hand. It goes round once a day.
• Top of the dial is solar noon: the sun at its highest where you are.
• Bottom is solar midnight.
• The marks round the rim are normal clock hours. The thick one near the top is 12.
• The small dot on the rim is the minute. It starts at the 12.

The face

• Day — sun above the horizon, from sunrise to sunset.
• Civil twilight — sun 0° to 6° below the horizon. Bright enough to see by.
• Nautical twilight — 6° to 12° below. Horizon still visible, brighter stars out.
• Astronomical twilight — 12° to 18° below. Dark to the eye. Only instruments can tell it from night.
• Night — sun more than 18° down. Stars, and the moon as it is tonight.

The short ticks inside the face: sunrise, sunset, solar noon, mid-morning, mid-afternoon. Tap the clock to show or hide the time.

Time zone

Location

Tide

A small blue dot on each hour mark shows the water at that hour. On the outer edge is the lowest astronomical tide, the zero of a tide table. At the inner end of the mark is 1 m. Each further mark-length in is another metre.

Sun times come from sunrise-sunset.org for your location and date. The moon and the tide are worked out on the phone; tide gauge constants from the Neaps tide database (TICON-4, CC BY 4.0, and NOAA). Far from any gauge, the tide comes from the Open-Meteo marine model instead. Not for navigation.

Done