Abell 21 aka SH2-274 The Medusa Nebula (Roland Schliessus)

Celestial hemisphere: Northern · Constellation: Gemini (Gem) · Contains: HD59152 · HD59309 · NGC 2395 · PK205+14.1 · Sh2-274

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Abell 21 aka SH2-274 The Medusa Nebula

Link: http://www.roland-schliessus-astro.de/

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Abell 21 aka SH2-274 The Medusa Nebula

Link: http://www.roland-schliessus-astro.de/

Abell 21 or Sharpless 2-274, also known as the Medusa Nebula, is an expansive low surface brightness planetary nebula in the constellation of Gemini near the ecliptic. The nebula owes its proper name to the snake-like gas filaments, which are reminiscent of Medusa's hair.

It was independently discovered in 1955 by George Ogden Abell at Palomar Observatory and Hugh M. Johnson in the Yerkes-McDonald Survey. Until the 1970s it was also considered that it could be a supernova remnant. Based on the calculated rate of expansion and the thermal nature of the radio emission, Soviet astronomers concluded in 1971 that the original classification is the most likely.

The object is not to be confused with the galaxy cluster Abell 21 or the merging galaxies NGC 4194, which are also sometimes associated with Medusa's head due to their appearance.

========================= Source: Wikipedia ==========================

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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	6659211
PixInsight job	VY9U49DTN6YRUKW9KFU9EHH6AGE9G90J
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	07h28m59s.999
RA (top/left)	07h32m02s.112
RA (top/right)	07h28m23s.924
RA (bottom/right)	07h25m57s.267
RA (bottom/left)	07h29m35s.358

Dec (center)	+13°18′57″.15
Dec (top/left)	+13°16′34″.60
Dec (top/right)	+14°02′32″.18
Dec (bottom/right)	+13°21′12″.61
Dec (bottom/left)	+12°35′23″.19

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Abell 21 aka SH2-274 The Medusa Nebula

Abell 21 aka SH2-274 The Medusa Nebula

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Abell 21 aka SH2-274 The Medusa Nebula

Abell 21 aka SH2-274 The Medusa Nebula

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