Image center RA: 21h39m17.42s DE:+57°32'14.3" Field of view 3 X 4.5 degrees.
Celestial North up, East left.
This cloud of gas and dust in the constillation Cepheus about 2400 light years away.
The large red star at the top of the image is one of the largest super red giants that we know of. Its' diameter is greater than the orbit of jupiter.
This star is called Herschels' Garnet Star. On top of being a huge star it is also a variable star whose magnitude varies about 1.5 magnitudes over a 2 1/2 year period.
It is about 1500 light years away.
The nebula itself is seen because of the ionized oxygen, hydrogen, and sulphur.
The dark areas are due to matter which is not ionized (glowing). This material either absorbs or reflects visible light.
The ionizing energy comes from a group of rather young stars near the center of the photo. They are so tightly packed, they appear as one star.
Their radiation is rich in ultraviolet which causes the gasses to lumenese.