If you ignore small deviations, the lengths of day and night averaged over an entire year each exactly 12 hours. Small deviations are:
that Jet refraction of sunlight by the atmosphere makes the day a few minutes longer and the night a few minutes shorter, depending on your place.
that Earth’s orbit is not a perfect circle, so the seasons are not all exactly the same length and evens the longer summer days and shorter winter days (and just as for the nights) are not all the way out.
that Sunrise is usually defined as the time when the top of the solar disc, not the Middle by the horizon goes. This makes the day a few minutes longer, depending on your place.
that the seasons not all just start in the middle of the day, so the amount of half day in summer and winter half of the year are not exactly alike, and just as for the amount of night.
I don’t know exactly how big these effects are so fast, but I expect them to not exceed a few minutes (except maybe close to the Poles).
On the dark days for Christmas is it lets light and dark early; we can still have peace with it. But why does it take so long to catch the morning light is?
Monday, december 21st, the shortest day of this calendar year; the astronomical winter begins on that day to 18.47 hours. Seven hours and four and forty minutes after sunrise turns up the Sun below the horizon again. Then the days already in the morning there is little of slings, to notice. For the time being, the even later still something light. The gain in day length is as yet only achieved at the end of the day. With Christmas comes the Sun four minutes later under than at the beginning of winter. Mid-January is the half an hour longer in the afternoon light. Only on 4 February also takes the morning half an hour longer than on the shortest day. Then the extension some more right on: every day of February both the morning and the evening there in about two minutes.
Clock is no good
The duration of the daylight period, the time between sunrise and sunset, as we know, varies with the seasons. The Sun on the shortest day of the year the last rises and the earliest goes down. However, this is not the case. Darkness fell on 13 december, the earliest in more than two weeks before the date of the shortest morning: 29 december.
This irregular behavior of the rise and set times of the Sun is a result of the way the clocks time is fixed. Hours and minutes are units of time with a thoroughly, constant time duration. This constant hours and minutes are used to the varying length of the day in equal parts: an impossible and thereby doomed task.
For example, a day is the length of time that elapses between the moment the Sun today in the South stands and time that this is the case again tomorrow. Such a solar day, which should last exactly 24 hours, however, in the course of the year varies in length. Most of a day consists of the time that the Earth needs to make her own axis a rotation; This time is more or less constant. At the same time, however, the earth revolves around the Sun. One such rotation of 360 degrees around the Sun takes one year, which approximately corresponds to an arc degree per day. That one degree must therefore extra around the Earth run before the observer sees the Sun in the South. That rate is about four minutes.
The speed at which the Earth moves along its course, however, varies as a result of the ellipse form of this job. The mentioned four minutes are therefore not exactly four minutes, but the one time some more, other times a bit less. The cooks cannot meet: an hour takes an hour and no second longer or shorter.
Satellite images of the shortest (above) and the longest day. The sensor on the satellite measures the solar radiation reflected by clouds and the Earth’s surface. In white areas is much solar radiation reflected, in dark blue almost none; Green tones are in between. On the shortest day is the North Pole dark; There is no solar radiation reflected. On the longest day of the northern hemisphere is precisely the Antarctic remains dark. Antarctica reflects more sunlight than the Arctic, where in summer the Arctic Ocean and the seas edge partly consist of open water without sea ice.
Length of Days Daylight and Night on Earth Length of Day at Equator Day Length by City Length of Day by Latitude Actual Length of Day Length of Day Animation Hours of Night Time.