Sagittarius Star Cloud - M24 (Massimo Di Fusco)

Sagittarius Star Cloud - M24

Messier 24 (also known as the Sagittarius Star Cloud M24 and IC 4715) is a large Milky Way star cloud in Sagittarius constellation that lies at an approximate distance of 10000 light years from Earth and has an apparent magnitude of 4.6. It is about 600 light years wide and lies in the Sagittarius Arm of our galaxy, the next inner spiral arm to our own. It occupies an area 90 arc minutes in apparent diameter and contains different types of objects, including stars and clusters that lie at a distance of 10000 to 16000 light years from Earth, which gives the cloud a significant depth. In the night sky, the star cloud appears about nine times larger than the full Moon.
Messier 24 is one of the three Messier objects that aren’t deep sky objects (despite it contains many deepsky objects). The other two are the double star Winnecke 4 (WNC 4) in Ursa Major, catalogued as Messier 40, and the asterism Messier 73, formed by four stars that aren’t physically associated with each other, found in Aquarius constellation.

M24 contains NGC 6603, a faint open cluster of about 30 stars, located in the brightest region of the star cloud. The cluster was discovered by the English astronomer John Herschel between 1825 and 1833. It has a visual magnitude of 11.4 and is some 9400 light years distant.
The Sagittarius Star Cloud contains several dark nebulae which are easy to observe because of the bright background that M24 provides. The most prominent of these is Barnard 92, an oval-shaped dark nebula stretching across a quarter of a degree that got the nickname the Black Hole before the term started to be used for black holes as we know them now. The dark nebula was discovered by the American astronomer Edward Emerson Barnard in 1913. It was one of the first objects of its kind discovered by Barnard. M24 also contains the dark nebulae Barnard 93, Barnard 304 and Barnard 307.
Messier 24 is also home to two additional clusters, considerably fainter than NGC 6603. The clusters lie in the vicinity of the two larger dark nebulae. Collinder 469 is located near the lower right end of Barnard 92, while Markarian 38, also catalogued as Biur 5, lies to the south of Barnard 93.
The Sagittarius Star Cloud also contains two planetary nebulae, catalogued as NGC 6567 and M 1-43, and several variable stars.

Only recently, with the use of narrowband filters and long exposure photography, the supernova remnant SNR G013.3-01.3 and StDr 156 were discovered in the field of M24 as well as a lot of ionized Hydrogen and Oxygen.

Anyway, I preferred to shown the RGB version as final and the HOO version at mousehover.

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Status	Advanced success
Started	...
PixInsight job	R2ZQ3LBYN3J25HNTZHJX1E64RP3KUEBA
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	18h18m15s.52
RA (top/left)	18h09m53s.40
RA (top/right)	18h26m11s.39
RA (bottom/right)	18h26m29s.52
RA (bottom/left)	18h10m27s.50

Dec (center)	-18°39′55″.6
Dec (top/left)	-19°50′58″.3
Dec (top/right)	-20°00′17″.5
Dec (bottom/right)	-17°27′30″.8
Dec (bottom/left)	-17°18′21″.10

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