A stunning Emission Nebula, 10k light years far from us

Sharpless 132, an extensive Emission Nebula visible in the Cepheus constellation

In this image, taken by Nicolas Kizilian using a William Optics Zenithstar 66 Telescope and a Moravian G2-8300 camera, you can see Sharpless 132 (Sh2-132,The Lion Nebula), an HII region type emission nebula in the constellation of Cepheus, about 10,400 light-years away from Earth.

The nebula is ionized by a bunch of hot and massive stars with strong ultraviolet radiation, most notably the two Wolf-Rayet stars HD 211564 and HD 211853.

The bubble-like structure you can see is most likely caused by stellar winds of massive stars.

Visible at the very right side center of the image is the small open cluster Berkeley 94. In the bottom left you can see the open cluster NGC 7235.

In the top right you can see a small red ring-like feature called Abell 79, most likely a planetary nebula.

What is an emission nebula?

An emission nebula is a cloud of ionized gas (often by ultraviolet radiation from nearby stars) emitting light of various colors, in case of HII mostly reddish-pink (if viewed in natural colors).

What is a Wolf-Rayet star?

Wolf-Rayet stars are massive stars that have extremely high surface temperatures of 30,000 K to around 200,000 K. They are also very luminous, some of them several million times more luminous than our Sun, although much of their radiation output is in the ultraviolet part of the spectrum and not the visible part.

They blast strong winds of particles out into space while burning up their fuel, lasting only a few hundred thousand years, a short life for a star.

What is a planetary nebula?

A planetary nebula is an emission nebula, it is basically a shell of glowing ionized gas ejected from old red giant stars and driven by the ultraviolet radiation of the resulting young and hot white dwarf. They are short-lived objects, lasting a few tens of thousands of years until the white dwarf has cooled down so much that its not putting out enough ultraviolet radiation anymore and the gas no longer gets ionized.

Credits P.Markuse