M78 is a cloud of interstellar dust located about 1,600 light years from Earth. It is illuminated over an expanse of four light years by the by the energy of its embedded, bright blue, early B-type stars which emit a continuous spectrum. In the area are 45 low mass stars with hydrogen emission lines.
M78 is the brightest diffuse reflection nebula in the sky. A reflection nebula contains very little ionized gas and merely reflects the light of the nearby stars. Messier 78 contains about 45 T Tauri variables. These are very young, pre-main sequence stars, typically found near molecular clouds, that are still in the process of contracting to the main sequence. The nebula is also home to about 17 Herbig-Haro objects, small patches of nebulosity that form near young stars when these eject jets of gas which then collide with the nearby dust and gas at high velocities. Herbig-Haro objects are commonly found in star forming regions, with several often forming around a single star. They typically only last for several thousand years before dispersing.Messier 78 was discovered by Charles Messier’s colleague Pierre Méchain in early 1780.
Messier added the nebula to his catalogue of deep sky objects on December 17 of that year.

In this image you can see part of Barnard’s Loop…
Barnard's Loop is an emission nebula in the constellation of Orion. It is part of the Orion molecular cloud complex which also contains the dark Horsehead and bright Orion nebulae. The loop takes the form of a large arc centred approximately on the Orion Nebula and can be seen with the naked eye.
Bright young stars in Orion may have produced “winds” that created it. Or long-gone supernovae may have blasted it out.
No one knew this area of space existed until E. E. Barnard discovered the loop in 1894 on some of the first long-exposure photos.

The was processed using this workflow in Pixinsight and Photoshop…
WBPP
BlurXTerminator
Ez Soft Stretch
NoiseXTerminator (needed early in this edit)
StarXTerminator
LRGB Combination
Ha added through Pixelmath (thank you Bill Blanshan)
Multiple Colour Masks (adjusted with Clone Stamp for the Blue emission region)
Layers and Camera Raw Filter in Photoshop
Stars added back in Pixinsight using Star Mask

Hope you like it and…
Clear Skies!
Olly