LBN437, the Gecko Nebula

There is a large Hydrogen Alpha region in constellation Lacerta named SH2-126. In one spot this is obscured by a large molecular cloud, named LBN437, resembling a lizard looking across an edge. Its common name is therefore Gecko Nebula.

While the molecular cloud itself seems to be pretty bright, from an astronomical standpoint it still is classified as a dark nebula, obscuring objects behind.

A bright star way outside the frame not only excites the Hydrogen molecules to glow, but as well illuminates the molecular cloud and exposes its very fine details. As well interesting is the glow of Hydrogen around the sharp front edge of the molecular cloud bottom left.

The fine structures extend way beyond the crop shown above:

Aside these prominent elements, several other objects are hiding in this interesting area. Looking closely, you may spot a real reflexion nebula right in the middle of the bright triangular area. This is caused by the tiny Herbig-Haro Object, gas ejected by a young star interacting with molecular matter. As a regular phase within star creation these objects are relatively short-lived in astronomical terms and outlast just a few thousand years.

Here is just another detail of this interesting region:

For astrophotography this is primarily a LRGB object, so quite much exposure time was invested to get the fainter details as clear as possible. As a result the three times four hour RGB stack already looks pretty neat without any editing:

In order to express the level of detail I intended to go with, let's compare the raw RGB stacks containing 3x 1.2 hours and 3x 4 hours of integration time. While the prominent structures already look good with the shorter exposure time, it is pretty obvious that the AI-based tools have to guess less on the fainter parts with the longer integration time. When checking the stack from the 2x 2 hours exposure time, I decided it was worth to spend another 6 hours on R/G/B.

In addition we also obtain a better separation from the background and much smoother color transitions.