Sh 2-155, from the Sharpless catalog, also known as the Cave Nebula, is a diffuse nebula in the constellation Cepheus, within a large nebula complex containing emission, reflection and dark nebulae. Sh 2-155 is an ionized H II region with ongoing star formation activity, at an estimated distance of 2400 light-years from Earth.
Technical details, high resolution and annotated versions available on Telescopius: https://telescopius.com/pictures/view/199742/deep_sky/sh-2-155/by-drgfreeman
Image license: CC BY-NC-SA 4.0.
#astrophotography #astronomy #photography #astrodon #nebula #DeepSky #space #sh2-155 #RGBHa #KStars #ekos #phd2 #GIMP