M21/Trifid nebula in Sagittarius (Sigga)

Celestial hemisphere: Southern · Constellation: Sagittarius (Sgr) · Contains: B85 · M 20 · M 21 · NGC 6514 · NGC 6531 · Sh2-30 · Trifid nebula

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M21/Trifid nebula in Sagittarius

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M21/Trifid nebula in Sagittarius

Messier 21 or M21 (also designated NGC 6531) is an open cluster of stars in the constellation of Sagittarius. It was discovered and catalogued by Charles Messier on June 5, 1764.

M21 is a relatively young cluster of a mere 4.6 million years of age. It is tightly packed but contains about 57 stars. A few blue giant stars have been identified in the cluster, but Messier 21 is composed mainly of small dim stars. With a magnitude of 6.5, M21 is not visible to the naked eye; however, with the smallest binoculars it can be easily spotted on a dark night.

--Wikipedia

More:

Messier21 - Wikipedia

Messier21 - Astropixels.com

Messier21 - SEDS

This is image #18 in long term project to photograph the complete Messier catalog. This turned out better than I expect, more exposures for longer period plus M20 in same field.

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Description: Revision using different parameters in DSS.

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Unknown

The “AstroBin Image of the Day and Top Picks”, or IOTD/TP, is a long-running system to promote beautiful, interesting, peculiar, or otherwise amazing astrophotographs, with a focus on technical excellence. Learn more.

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Views by Submitters (available since September 19th, 2023) Every image is assigned to 50% of available Submitters. In the event that at least 80% of them don't view the image before its time in the IOTD/TP process expires, it's assigned to the other 50% of Submitters and the process begins anew.
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Status	Advanced success
Started	...
Astrometry.net job	1589137
PixInsight job	7F796DWH2M21W0PLAXMWC7CF5UF71QOF
PixInsight queue size	n/a
PixInsight stage	n/a

RA (center)	18h04m14s.55
RA (top/left)	18h00m50s.99
RA (top/right)	18h07m55s.56
RA (bottom/right)	18h07m36s.52
RA (bottom/left)	18h00m35s.96

Dec (center)	-22°28′38″.5
Dec (top/left)	-23°07′42″.5
Dec (top/right)	-23°02′31″.6
Dec (bottom/right)	-21°49′19″.6
Dec (bottom/left)	-21°54′29″.6

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M21/Trifid nebula in Sagittarius

M21/Trifid nebula in Sagittarius

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M21/Trifid nebula in Sagittarius

M21/Trifid nebula in Sagittarius

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