Part of a 15-panel mosaic…
This image is part of a larger project that is a 5×3 mosaic that includes the Lagoon (M8) and Trifid (M20) Nebulae. The work will likely continue into next year since these nebulae are so low in the sky and for a short amount of time in the northern hemisphere at this time of year.
I like how this turned out, and is definitely an improvement on the image of the off-center and unprocessed image I posted on May 23. This image is comprised of 1070 10-second subs captured using the ZWO Seestar S50 in Alt-Az mode with a 50% overlap over 4 evenings in Bottle 6 skies. I used Stellarium to determine the center star of the mosaic, then AstroMosaic (ruuth.xyz) to determine the correct number of panels and overlap, Astrometry to determine the center coordinates of panels for re-shooting, and the Seestar-alp python script and Seestar_alp front-end running on a Raspberry Pi 4B to control the Seestar remotely. I used Siril for Background Extraction, Photometric Color Calibration, and Generalized Hyperbolic Stretch, and Color Saturation, Topaz for Noise Extermination and de-blurring, then Photoshop for star reduction and finalizing
Description, Distance, and Measurement
The Lagoon Nebula (catalogued as Messier 8 or M8) is a giant interstellar cloud in the constellation Sagittarius. It is classified as an emission nebula. The nebula contains a number of dark, collapsing clouds of protostellar material. It also includes a funnel-like structure caused by a hot O-type star that emits ultraviolet light, heating and ionizing gases on the surface of the nebula. The nebula also contains at its centre a structure known as the Hourglass (so named by John Herschel). The Lagoon Nebula is estimated to be between 4,000–6,000 light-years away from the Earth and has a dimension of 110 by 50 light years.
History
The Lagoon Nebula was discovered by Giovanni Hodierna before 1654 and is one of only two star-forming nebulae faintly visible to the eye from mid-northern latitudes. Seen with binoculars, it appears as a distinct cloud-like patch with a definite core.
