According yar.kp.ru, the time when the sun rises, barely go and even late at night sky quite bright. It appears, in this season, in addition to short night there is another beautiful and mysterious natural phenomenon — the so-called noctilucent clouds. The naked eye and can be seen only in the summer in a strip of white nights, which includes Yaroslavl, and just after sunset — from about midnight until three in the morning.
— The clouds can be seen directly in the city, go on nature is optional. True, they do not appear every night. They can be seen very well from our observatory, which is located at the eternal flame on the basis Yagma, and yet it is the center of the city — a member of the Yaroslavl explained the Society of Astronomy (Jarolim) Alexander Sabitov.
Astronomers have studied the subject for many years and have collected a large photo collection of noctilucent clouds, but the cause of their appearance is still a mystery. It is well established only that the appearance of such clouds coincides with the cycle of solar activity.
The word "cloud", by the way, describes the likely appearance, and not the nature of the phenomenon. For example, one of the most popular versions of such "cloud" — a meteor dust, burnt down in the upper atmosphere. On the other — and at an optical illusion, a sort of mirage.
Yaroslavl astronomers often call this phenomenon simply "silver" and loved.
— Silver — it is very beautiful! I am seven years in Jarolim, and every summer we go expedition observation of noctilucent clouds. Our permanent head Tatyana Korovkin always does a lot of great pictures — smiling Alexander.