Sun and moon planner
Plan the light for a place and date: sunrise and sunset, golden and blue hour, civil, nautical and astronomical twilight, the sun's azimuth and elevation through the day, and moonrise, moonset, phase and illumination — with a day chart and a sky compass, in the place's own time zone.
Added
How to use it
Pick a City, type a Lat / lon with its time zone, or choose Here and tap Use my location (the browser asks first; your position stays in this browser and is never put in a share link). Choose the date with the arrows or the date box; Today goes back to now. Times are shown in the place’s time zone, with summer time handled, so a plan for Tromsø made in California shows Norwegian clock times.
Day lists the day’s light in order: astronomical, nautical and civil dawn, blue hour, golden hour, sunrise (with its compass bearing), solar noon (with the sun’s height), sunset, and back down to astronomical dusk, plus moonrise and moonset. On today’s date the next event is highlighted and those already past are dimmed. The chart plots the sun’s and the moon’s elevation through the day over bands coloured by the light; the sky compass is a view looking down with north up — the sun’s path in orange, the moon’s dashed, rays where they rise and set. Drag the time slider to see where both are at any moment, how long shadows are, and what kind of light it is.
⛶ Full screen (or F) gives the Day chart the whole screen with the time slider just above it
and the sky compass beside it on a wide screen — the browser’s full screen where it is allowed,
otherwise a full-window layer (iPhone); it is redrawn as the window changes, and ◫ Panels shows
the place and the event list. Escape leaves.
Moon shows the phase, the illuminated fraction, the age since new moon, its distance (a "supermoon" is a full moon near perigee, closer than about 360,000 km), today’s rise, highest point and set, the next eight principal phases, and a 30-day strip with rise and set times — for planning a moonrise over a skyline, or a moonless night for stars.
Table lists the sun’s and moon’s azimuth and elevation every 5 to 60 minutes; copy or download it as CSV.
The bands, by the sun’s geometric elevation:
| Light | Sun’s elevation |
|---|---|
Golden hour |
−4° to +6° (warm, low, soft light) |
Blue hour |
−6° to −4° |
Civil twilight |
0° to −6° (sunrise and sunset use −0.833°: the upper edge of the disc on the horizon, with refraction) |
Nautical twilight |
−6° to −12° |
Astronomical twilight |
−12° to −18° |
Night |
below −18° |
Golden and blue hour have no official definition; these limits are the common photographers' choice. Near the poles and around midsummer a "golden hour" can last most of the evening, and at high latitudes in summer there is no astronomical night at all — the page says so.
How it is calculated
The sun uses the equations of NOAA’s Solar Calculator (after Jean Meeus, Astronomical Algorithms, 2nd ed., 1998), with NOAA’s refraction approximation. The moon uses Meeus’s chapter 47 series (the largest 39 terms in longitude and distance and 30 in latitude), the rising rule of chapter 15 (the centre at 0.7275 × parallax − 34′), and the illuminated fraction of chapter 48. Events are found by scanning the local day every 10 minutes and bisecting each crossing to a second, which also handles midnight sun, polar night and days when the moon does not rise or set.
Checked against the US Naval Observatory’s Sun and Moon Data for One Day for Greenwich, New York, Sydney, San Francisco, Tokyo and Tromsø (summer and winter): sun times agree to the minute and moon times within one or two minutes; against Meeus’s worked examples 25.a, 47.a and 48.a; and against USNO’s dates of the full moon of 23 April 2024 (23:49 UT) and new moon of 8 April 2024 (18:21 UT), within three minutes.
Limits
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Times are for a level, sea-level horizon. Mountains, buildings and trees delay sunrise and bring sunset forward; elevation above the surroundings makes them slightly earlier/later.
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Refraction is the standard average; on very cold or hot days near the horizon it can shift sunrise and sunset by a minute or two — almanacs only promise about a minute.
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The moon’s position is good to roughly 0.01°, plenty for planning, not for occultations or eclipse contact times.
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Azimuths are from true north. A magnetic compass differs by the local declination — the compass tool can show true north.
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The moon picture shows the lit side as seen from the northern hemisphere.
Related: night-sky photography (500 and NPF rules, star trails, the Milky Way core), exposure (Sunny 16 and light levels), depth of field, flash, EXIF statistics, compass and level, time zones.
Linking to an example
Links can be written by hand. Add the tab after #: day, moon or table.
| Parameter | Meaning | Example |
|---|---|---|
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Where: |
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A city id: |
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Latitude in degrees, north positive |
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Longitude in degrees, east positive |
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IANA time zone for typed coordinates |
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The date, |
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Time of day for the slider and moon details, |
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Table interval in minutes: |
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One of the presets below; parameters given with it override the preset’s |
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Presets:
example= |
Shows |
|---|---|
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London on the June solstice: sunrise 04:43, sunset 21:21 BST, and no astronomical night (open) |
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Tromsø at midsummer: the sun never sets (open) |
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Tromsø at midwinter: no sunrise, but four hours of civil twilight around noon (open) |
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New York on the shortest day: sunrise 07:17, sunset 16:32 EST (open) |
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Sydney at the March equinox: sunrise almost due east, sunset almost due west (open) |
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The full moon of 23 April 2024 rising over San Francisco at 20:00, just after sunset (open) |
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Yosemite Valley in the October golden hour, with the sun’s path on the compass (open) |
Typed coordinates: sun-moon/?loc=typed&lat=46.5584&lon=7.8352&tz=Europe/Zurich&date=2025-07-01#day.
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