At the summer solstice, the sun is at its highest point.
It's the longest day of the year - and the shortest night too.
In some cultures this is a reason to celebrate.
Berlin (dpa) - In Germany, Europe and the entire northern hemisphere, June 21 is the longest day of the year.
While for meteorologists summer already began on June 1st, the solstice marks the beginning of summer according to astronomical definition.
The sun is then at its highest point over the northern hemisphere.
In Scandinavia, for example, the day is even considered the center of summer - with corresponding rituals.
The solstice falls on the same moment all over the world
The exact local times differ depending on the time zone.
This year the date falls on June 21 at 5:32 a.m. in Berlin and on June 20 at 11:32 p.m. in Montreal, Canada.
But that is the same point in time.
The event is defined according to the moment at which the sun is vertically above the tropic of the tropics - regardless of time zones and coordinates.
The earth is further from the sun in June than it is in December
People in the northern hemisphere look forward to the beginning of the warmest and brightest season at the solstice.
In June, the distance between the earth and the sun is around 5 million kilometers greater than at the winter solstice in December.
The reason: Our planet does not move on a circular path around the sun, but on an elliptical one.
In addition, the sun is not exactly in the center of the orbit.
It is warmer in summer because in June the North Pole is tilted towards the sun and the northern hemisphere receives more sunlight and heat.
At night the sun shines on the Arctic Circle
June 21st is the only day of the year on which the sun does not set within the entire Arctic Circle.
The closer you get to the North Pole, the more nights with the so-called midnight sun there are around the date.
In fact, the celestial body is partially visible all night even south of the Arctic Circle.
Its rays are deflected by the earth's atmosphere in such a way that the sun shows itself even when it is just below the horizon.
Depending on the air pressure and temperature, this effect can be so strong that the midnight sun can even be seen around 100 kilometers beyond the Arctic Circle.
The summer solstice brings a festive mood
For many Scandinavians, the so-called midsummer is roughly what carnival is for some Germans: an all-encompassing festival where work is left behind, the glass is raised and everything else is simply forgotten for a few days.
Midsummer is one of the biggest days of the year for them, some even consider it the only true national holiday.
The evening is especially sacred to Swedes.
For them, it's usually a time of salmon, brandy, and dancing around the midsummer pole.
For the Finns, the day often marks the start of the summer vacation.
There is also a traditional celebration every year in Stonehenge, England.
In the time before Corona, around ten thousand people visited the stone colossi of the Neolithic every year during the solstice.
© dpa-infocom, dpa: 210620-99-68484 / 2
Stonehenge Official Website - English
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House of Astronomy
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