M8/M20 Region
Lagoon & Trifid Nebula, Emission/Reflection/Dark Nebula & Open Cluster, Sagittarius
The Lagoon Nebula (catalogued as Messier 8 or M8, NGC 6523, Sharpless 25, RCW 146, and Gum 72) is a giant interstellar cloud in the constellation Sagittarius. It is classified as an emission nebula and as an H II region, and can be seen below center in this image. The Trifid Nebula (catalogued as Messier 20 or M20 and as NGC 6514) is an H II region in the north-west of Sagittarius in a star-forming region in the Milky Way’s Scutum-Centaurus Arm. It can be seen above center in this image. Messier 21 or M21, also designated NGC 6531 or Webb’s Cross, is an open cluster of stars located just above and left of M20 in this image. Sharpless 29 (Sh2-29) is listed in the Sharpless catalogue of H II regions: interstellar clouds of ionised gas, and star formation. It is located about 1.25 degrees (left) north-east of the larger Lagoon Nebula in this image.
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. Within the nebula is the open cluster NGC 6530. The Lagoon Nebula is estimated to be between 4,000–6,000 light-years away from the Earth. In the sky of Earth, it spans 90′ by 40′, which translates to an actual dimension of 110 by 50 light years. The nebula contains a number of Bok globules (dark, collapsing clouds of protostellar material), the most prominent of which have been catalogued by E. E. Barnard as B88, B89 and B296. It also includes a funnel-like or tornado-like structure caused by a hot O-type star that emanates ultraviolet light, heating and ionizing gases on the surface of the nebula. The Lagoon Nebula also contains at its centre a structure known as the Hourglass Nebula (so named by John Herschel).
The Trifid Nebula was discovered by Charles Messier on June 5, 1764. Its name means ‘three-lobe’. The object is an unusual combination of an open cluster of stars, an emission nebula (the relatively dense, reddish-pink portion), a reflection nebula (the mainly NNE blue portion), and a dark nebula (the apparent ‘gaps’ in the former that cause the trifurcated appearance, also designated Barnard 85).
M21 was discovered and catalogued by Charles Messier on June 5, 1764. This cluster is relatively young and tightly packed. A few blue giant stars have been identified in the cluster, but Messier 21 is composed mainly of small dim stars. Although he cluster is positioned near the Trifid nebula (NGC 6514), it is not associated with that nebulosity. It forms part of the Sagittarius OB1 association. The cluster is located 1,205 pc away from Earth with an extinction of 0.87, and is around 6.6 million years old.
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. Within the nebula is the open cluster NGC 6530. The Lagoon Nebula is estimated to be between 4,000–6,000 light-years away from the Earth. In the sky of Earth, it spans 90′ by 40′, which translates to an actual dimension of 110 by 50 light years. The nebula contains a number of Bok globules (dark, collapsing clouds of protostellar material), the most prominent of which have been catalogued by E. E. Barnard as B88, B89 and B296. It also includes a funnel-like or tornado-like structure caused by a hot O-type star that emanates ultraviolet light, heating and ionizing gases on the surface of the nebula. The Lagoon Nebula also contains at its centre a structure known as the Hourglass Nebula (so named by John Herschel).
The Trifid Nebula was discovered by Charles Messier on June 5, 1764. Its name means ‘three-lobe’. The object is an unusual combination of an open cluster of stars, an emission nebula (the relatively dense, reddish-pink portion), a reflection nebula (the mainly NNE blue portion), and a dark nebula (the apparent ‘gaps’ in the former that cause the trifurcated appearance, also designated Barnard 85).
M21 was discovered and catalogued by Charles Messier on June 5, 1764. This cluster is relatively young and tightly packed. A few blue giant stars have been identified in the cluster, but Messier 21 is composed mainly of small dim stars. Although he cluster is positioned near the Trifid nebula (NGC 6514), it is not associated with that nebulosity. It forms part of the Sagittarius OB1 association. The cluster is located 1,205 pc away from Earth with an extinction of 0.87, and is around 6.6 million years old.
Telescope: Askar FRA300pro f5
Mount: Astro Physics Mach-1
Camera: ZWO ASI6200MC pro
Guider: ZWO Off-Axis-Guider / ZWO120MM Mini
Filters: Optolong UV/IR Cut Filter (Luminance)
Lum: 48×5 mins = 240 mins
Total Imaging Time: 4h 00m
Data Imaged remotely over 3 nights during June 2023.
Data acquisition & Processing by David Churchill.
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