White Nights have long been a visiting card andone of the main attractions of St. Petersburg. This unusual natural optical phenomenon is observed in the city on the Neva every year from June 11 to July 2. At this time, the center of the solar disk falls at midnight below the horizon by no more than seven degrees, which causes a fairly high level of illumination for this time of day.
The geography of this unusual natural effect.quite extensive. White nights are observed at the beginning of the summer period in both hemispheres at latitudes exceeding sixty degrees. But in our mind they have long become a symbol of St. Petersburg. At this time, the city as if not sleeping, watching the magic sketches of nature. There are many concerts, festivals, performances. It seems that the whole city is immersed in the magic of natural effects. At this time, a huge number of tourists come here, as well as music and cinema stars from around the world.
Every year in northern Palmyra in June passesrock festival with a very symbolic name "White Nights in St. Petersburg." Also at this time there is an international cinema competition, where films shot during the year are shown. The days of the white nights in Europe’s largest non-capital city are marked by an extremely rich and intense cultural life. This is a magical holiday, presented by nature itself, which is also one of the tourist lures of the city on the Neva. St. Isaac's Cathedral on a white night looks especially impressive.
What is this phenomenon withan astronomical point of view and what is the mechanism of its formation? The term "white nights" is usually denoted the qualitative characteristics of twilight, for which a sufficiently high level of natural light is characteristic. In fact, during the period close to the summer solstice in the Northern Hemisphere, evening twilight merges with the morning. The process of movement of our planet in its orbit is associated with a change in the angle of inclination of the earth’s axis by a certain number of degrees. As a result, the North Pole moves to the perihelion point, which is accompanied by almost perpendicular incidence of sunlight on the surface of the planet in the polar regions. This causes such unusual optical effects, which came into use under the name "white nights".
Такое природное явление в России характерно не only for St. Petersburg, but also for Murmansk, Norilsk, Vorkuta, Cherepovets, Vologda, Magadan, Nizhnevartovsk, Khanty-Mansiysk, Nefteyugansk, Surgut, Yakutsk, Arkhangelsk and many more cities and regions located north of the sixtieth parallel. In addition, this effect was observed at latitudes closer to the equator, which was caused by the fall of the Tungussky meteorite. After that, on the territory of many European countries and in Russia, it was possible to observe various optical anomalies, including the so-called bright dawns and white nights, which are absolutely not characteristic of these regions.
Outside Russia, this phenomenon is also not sorarity. Finland, for example, is generally considered the edge of the white nights. This natural optical effect is also characteristic of northern Sweden, Iceland, Norway, the polar regions of Canada, Greenland and even Estonia. In the UK, white nights can be observed on the Orkney Islands.
