The night between Sunday and Monday will be the longest. Monday will be the shortest day, which in the Stockholm area means that the sun bothered to stay above the horizon in just over six hours.
– Right now we are leaning in the northern hemisphere away from the sun, says Lovisa Andersson, meteorologist at SMHI.
December 00:03 is the winter solstice.
Above the Arctic Circle prevailing during the weeks around the winter solstice night darkness all days, so-called polar night, because the sun does not address itself above the horizon.
Although the winter solstice thus occurs on December 22 could be the earliest sunset is already seen in mid-December, around a week before the winter solstice. The latest sunrise occurs a few days after the shortest day. The explanation, writes SMHI on its site, is that the earth does not move at a steady rate around its own axis. This in turn depends partly on the Earth’s orbit around the sun is elliptical, and how the Earth’s axis is tilted.
This means to earth some day go faster on its axis than other days, from the Earth perceived as the sun goes faster across the sky. This means that the time between the sun is due south from one day to another is rarely exactly 24 hours. However, the cut in a year exactly 24 hours.
On one day, the difference can be at most a little under half a minute, but it is estimated up the difference over several weeks, it can at most vary over quarter before variations begins go the other way again.
In November, the sun is present in about fifteen minutes. The turning point occurs precisely in December and January and February, the sun slowly than an imaginary medelsol that takes exactly 24 hours in which to go round the earth. This means that both sunrise and sunset occur a little earlier before the winter solstice.
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