Lagoon - (Sagittarius Special I)

Sagittarius is one of the jewels of the summer sky in the northern hemisphere as it points towards the core of our galaxy. It is a rich region in all kind of deep sky objects and I never get tired or jumping through this area even with my binoculars. One of this awesome objects is the Lagoon nebula.

The Lagoon Nebula (catalogued as Messier 8 or M8, and as NGC 6523) is a giant interstellar cloud classified as an emission nebula. It is one of only two star-forming nebulae faintly visible to the naked eye from mid-northern latitudes. Seen with binoculars, it appears as a distinct oval cloudlike patch with a definite core. A fragile star cluster appears superimposed on it.

The Lagoon Nebula is estimated to be between 4,000-6,000 light years from the Earth. In the sky, it spans 90' by 40', translates to an actual dimension of 110 by 50 light years with an apparent magnitude of 6.0.

On top of the nebula, there is a star cluster known as NGC 6530. This is a young cluster of about 2,000,000 years. 

The picture is composed of 35 lights of 150" each, 35 darks and 40 bias, taken through the 70 mm refractor (ETX-70) mounted on the HEQ-5 (tracking not-guiding) and with the unmodded Nikon D3100 DSLR. The stacking was performed with DeepSky Stacker and processed with StarTools and Photoshop. The new workflow I'm following allows me to constrain the stars and its halo enhacing the main subject in the frame.

Enjoy!

 

And the annotated image as usual: