Facts about Deneb
The star Deneb can't be missed with an apparent brightness of 1.25mag. Since measuring the distance of Deneb is difficult, it is estimated to be about 1,000 to 3,000 light-years away. Furthermore, despite its far distance, Deneb is very bright in the night sky, shining 250,000 times brighter than the Sun. Also, its diameter is about 200 times that of the Sun, making Deneb one of the largest known stars of spectral class A that can be seen with the naked eye. Additionally, the star Deneb has a surface temperature of 8,400 Kelvin as well as it is 250 times the size of the Sun and has about 22 times the mass.
Furthermore, Deneb is currently in the transition stage from a blue giant to a red supergiant. This means that it is getting redder but also more luminous as its diameter increases. Accordingly, it will soon have reached the end of its life and will end as a supernova in a few million years. Deneb also has a companion star, but there is no further information about it yet.