Sun times in London, United Kingdom

Sun times are the key moments of the solar day for a place and date: sunrise and sunset, solar noon, day length, the golden and blue hours, and the civil, nautical and astronomical twilight phases. They depend on your latitude, longitude and the date, so they shift through the year and differ from one location to the next.

Golden hour is the period of soft, warm light when the sun is low — roughly from sunrise up to 6° above the horizon in the morning, and from 6° down to sunset in the evening. Its length depends on latitude and season: near the equator it can be 30–40 minutes, while in high-latitude summers it can stretch well over an hour.

Blue hour is the cool, even twilight before sunrise and after sunset, when the sun sits roughly 4–8° below the horizon. The sky takes on a deep blue tone that photographers prize for cityscapes and landscapes.

They are defined by how far the sun is below the horizon. Civil twilight runs to 6° below (enough light for most outdoor activity), nautical twilight to 12° (the horizon is still visible at sea), and astronomical twilight to 18° below, after which the sky is fully dark. At high latitudes in summer the sun may never reach these depths, so some phases simply do not occur.

Solar noon is the moment the sun is highest in the sky and due south (in the northern hemisphere) or due north (in the southern hemisphere). It rarely lands at 12:00 on the clock — your time zone, longitude within that zone, daylight saving, and the equation of time all shift it.

The shadow ratio is the length of an object’s shadow relative to its height, given by 1 ÷ tan(sun altitude). A ratio of "2 : 1" means a 1-metre pole casts a 2-metre shadow. The lower the sun, the longer the shadow; at solar noon it is shortest, and below the horizon there is no finite shadow.

All times are shown in the local time zone of the selected location, including daylight saving. Because solar events are tied to the sun’s real position — not the clock — sunrise, sunset and especially solar noon drift relative to civil time depending on your longitude within the time zone and the time of year.