In the northern hemisphere the longest day - it is called the summer solstice - falls on June 21.On this day, the sun is on the horizon of 17.5 hours, if we take the breadth of Moscow.In St. Petersburg, daylight lasts altogether almost 19 hours from 24.
solar system is rather complicated.The orbit of the Earth relative to the Sun is not a perfect circle, it is elliptical, so at different times the Sun is from the Earth a little further or a little closer to her.The difference is small - 5 million kilometers, but it was she who, as well as the tilt of Earth's axis cause the daily and annual cycle.In the longest day - the summer solstice - the Earth is 152 million kilometers from its star.On this day, the sun is located at the highest point of earthly neboslokna - ecliptic.Starting from June 21 daylight starts to diminish gradually until December 21 will not reach its minimum, and then everything starts over again.
in the culture of many peoples of the longest day is still a holiday, it came from the depths of centuries.Ancient Slavs, Finns, Swedes, Balts, Germans and Portuguese celebrated, and in some places still continue to celebrate this day as the beginning or the middle of summer.For example, in Sweden in celebration of the summer solstice after night festivities girls supposed to collect 7 different colors and put them under your pillow to dream of narrowing.The Celts celebrated this day Lita - mid-summer.This holiday was directly related to the pagan sun worship.
In Russia analog of these events was the day of Ivan Kupala, which is celebrated a little later - 7 July.The Slavs also thought this day mystic and I think that on the night of 7 to 8 July fern blossoms, which may indicate the place where the treasure is hidden.In China, too, there is such a holiday - Syachzhi.In Latvia this holiday is called Midsummer, and, in general, is a day off.In the cities are processions and festivities, which end only with the first rays of the sun.
One of the most famous buildings, which still links the longest day of the year, is Stonehenge, vozvezdenny about 5,000 years ago.Every year, thousands of Britons and tourists going there and celebrate the beginning of summer, because in terms of astronomy, this is the beginning.
addition to the solstices, there is equinox.These days the light day and night on an equal amount of time, and such things happen 2 times a year: March 21-22 and September 22-23.
If you ask to find out how many really lasts the longest day, the answer is simple - six months.And this day is called the Arctic, while the remaining six months of the Arctic Circle reigns night.This phenomenon can be observed in both hemispheres.
It would seem that some importance - the longest day in the northern hemisphere.Why would celebrate such a day, and in general, with the invention of electricity man almost ceased to depend on such things as the presence of the sun in the sky.However, the reality is more complicated.Of course, now, after sunset necessarily go to sleep, but you can just turn on a table lamp or chandelier.But still people are more like summer and sunny days than winter and overcast sky.
