Bubble mosaic: 4 Cas region including the Bubble Nebula, Salt & Pepper Cluster, Lobster Claw, Northern Lagoon, IC470 and Nova Cass 2021

[Padraic M]

A clear spell on 23/24/25 July gave an opportunity to capture a mosaic of a very rich area of Cassiopeia. This is a 2x1 panel mosaic in HaRGB which includes the following objects:

- Messier 52 Salt and Pepper Nebula, an open cluster discovered by Charles Messier on 1774.
- Caldwell 11 Bubble Nebula, an emission nebula surrounding a mag 8.7 star, which while it looks like a planetary nebula is actually a bubble blown by the star's stellar winds in the surrounding gas cloud. The bubble is 6 light years in diameter, and is at a distance of approximately 7,000 light years. It was discovered by William Herschel in 1787.
- Nova Cassiopeiae 2021, first eruption identified on 18th March and a number of flare-ups observed since. Imaged at mag 6.9 here and has since faded to mag 7.12.
- NGC7538 Northern Lagoon Nebula 
- Sharpless 2-157 Lobster Claw Nebula, emission nebula, which contains:
- -- Markarian 50 open star cluster
- -- Lynds' Bright Nebula (LBN) 537, from a catalog of bright nebulae compiled by Beverly Turner Lynds, a Professor of Astronomy at the University of Arizona, from a study of the red and blue prints of the National Geographic-Palomar Observatory Sky Atlas, and pubished in the Astrophysical Journal Supplement, vol. 12, p.163, 1965.
- -- Planetary Nebula PLN 110-0.1 (also WeSb 6 from the Galactic Planetary Nebulae catalog)
- NGC 7510 Dormouse cluster in Cepheus
- IC1470 H ii ionized region (emission nebula). "IC 1470 has a nebular spectrum similar to M8 and appears to be an H ii region excited by a single 07 star. It represents an object formed close to the edge of a molecular cloud, and its ionizing radiation is penetrating
the intercloud gas, producing a “blister” on its edge." (Lynds, B. T. ; Oneil, E. J., Jr.,  An optical study of IC 1470, Astrophysical Journal, Vol. 265, p. 803-807 (1983))

The image is processed HaRGB, and comprises two panels.

Panel 1:
R 10x300, 2x600
G 9x300, 2x600
B 9x300, 2x600
Ha 12x300

Panel 2:
R 9x300, 2x600
G 9x300, 2x600
B 9x300, 2x600
Ha 9x300

Total integration 7.6 hours in Bortle 2.

Equipment:
Imaging: SW Esprit 80; ZWO ASI1600mm Pro @ 20C gain 139 offset 21; Baader RGB and Ha 3.5nm filters. Capture controlled by NINA. Pixel ratio 1.9"/px.
Guiding: AA Starwave 50mm; ZWO ASI290mm Mini; PHD2.
HEQ5 Pro belt-mod
Processed by Astro Pixel Processor, Gimp and Noise Ninja.

Full detail on Astrobin

Annotated:

Edited July 30, 2021 by Padraic M

[astro mick]

A lot of work has gone into this and it shows.

A tad bright for me,but it is lovely.

Mick.

[carastro]

Oh wow, thanks for that Padraic, well done.  I was also extra excited as I realised that I accidentally unknowingly captured it myself when I was doing some random imaging checking my spacing about a week ago, so thanks for the annotated version.  Your image is tons better than mine as mine was only a short mono sub to test for corner stars, but luckily I still had the full frame, I would never have known if you hadn't posted.  

Carole 

 

Edited August 17, 2021 by carastro

[Padraic M]

Thanks Carole, I've seen the nova in a few images, I think there have been quite a few accidental captures recently! Nice to be able to identify it. It's a busy piece of sky.