The large bird spreads its wings on bottom of Milky Way. Deneb is the star of "tail", it is besides the translation in Arabic of this word. Located at 1500 Al, it is shining like 60000 suns, its temperature of surface is close to 10000 K This young, very massive blue giantess "burns" its fuel at high speed and should explode in 20 million years in supernova. Deneb is one of the headlights (magnitude 1,3) of our galaxy, in summer under our latitudes it is practically at the zenith on one of the tops of the triangle of summer.
Orphée which charmed the Gods with his quadrant was struck down by Zeus and taken the shape of a swan with its Quadrant at its sides. The Swan is called the cross of north, in opposition to the cross of south in the southern hemisphere. To notice towards the head of the Swan, a red giant pulsating star at the end of the lifetime Chi Cygni whose luminosity varies every 13 months.
In this constellation, at 2500AL the nebula of the veil , remainders of a supernova having exploded between 300000 and 50000 years ago and discovered by W Herschel in 1784. These gas veils are stretched in space at the speed of 120 km/s.
