Seahorse Nebula, Fireworks Galaxy and NGC6939 open cluster (Jérémie)

Seahorse Nebula, Fireworks Galaxy and NGC6939 open cluster

Nice weather is coming back !

It allowed me to test the Sigma Art 135mm f/1.8 in parallel with the TS Optics 71/347, both on the same mount, the Sigma with the ASI183MM Pro, and the 71/347 with the Canon EOS Ra.
It gives the same field of view, roughly, and allows me to capture Luminance data with one setup as well as RGB on the other one.

I wanted to try that on something difficult from the light polluted area where I live : Dark Nebulas. I chose Barnard 150 - The Seahorse Nebula, because the area is beautiful, with the Fireworks right next to it, as well as the open cluster NGC 6939. Full of colors...

Some informations about them :

The Seahorse Nebula also called Barnard 150 (named after astronomer Edward Barnard and his catalog), as well as LDN 1082 A, B et C (from astronomer Lynd, and another catalog... Lynd Dark Nebula).
It is a molecular cloud, that is to say an interstellar nebula, ~1200 light years away from us on the galactic disk, sufficiently dense and large to absorb light coming through it, and dense enough to form molecules (mostly H2).This is in these molecular clouds that stars birth. They account for less than 1% in volume of the interstellar medium, but contain 50% of the mass of gas that orbit between the center of the Milky Way and the orbit of the sun.

Next is the Fireworks Galaxy, also called NGC 6946. She was discorvered by Herschel (again) on September 9th 1798, and was later called Fireworks due to the high supernovae activity that was observed (since 1917). She's 40 000 ly wide (1/3 of the Milky Way, but with 1/2 the stars), and is distant of 25,2 millions ly.

Last but not least, the open cluster NGC 6939, distant of ~ 4000 ly, that would be ~ 1 billion years old...

I added a moon to scale in order to give a reference of the apparent size of these objects.

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Status	Advanced success
Started	...
Astrometry.net job	5861589
PixInsight job	EUE44IHTOZPMKP1F0NYBK8MGUTJKQ7LF
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	20h42m59s.43
RA (top/left)	21h00m15s.15
RA (top/right)	20h26m04s.89
RA (bottom/right)	20h27m02s.53
RA (bottom/left)	20h58m46s.31

Dec (center)	+60°08′01″.1
Dec (top/left)	+61°14′27″.6
Dec (top/right)	+61°18′46″.4
Dec (bottom/right)	+58°54′50″.5
Dec (bottom/left)	+58°49′15″.5

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