Archive for November 17, 2022

NGC 7184 Galaxy in Aquarius: November 2022 Observer’s Challenge Report #166

November 17, 2022

Work-File: Used only for organization and editing. When all entries are received (December 8th) and a final .pdf report will be issued by the 10th.

Roger Ivester: Observer from North Carolina

Object: Galaxy NGC 7184 in Aquarius

Date: October 14th 2022

Telescope: 10-inch f/4.5 EQ Newtonian 

Sketch Magnification: 104x

Field-of-View: 0.79º

Difficult and faint due to observing from my suburban back yard, over-looking the city of Boiling Springs.  I was using a light block curtain, to shield a pesky LED streetlight, to the east, about 1/4 mile away. The curtain eliminated that problem, but still looking over a light dome, due to its southerly position.  

Description:  Elongated slash, oriented NE-SW with a brighter central core, and a stellar nucleus.  With averted vision, I could see faint extensions arms, but only intermittently. 

Pencil Sketch as following:

“Keeping the ancient art of pencil sketching alive, for now and in the future of amateur astronomy.”

Mario Motta: Observer from Massachusetts

Taken with my 32-inch f/6.5, one hour Luminance, then one hour Blue, 30 mins. green, and 45 mins. red filters. I tried H alpha, but the signal was poor in that filter, so was not included in processing.

Taken with ZWO ASI6200 camera.

Phil Orbanes: Observer from Massachusetts

This barred spiral galaxy is at least 100 million light years in distance, therefore it is twice as far as the galaxies in the Virgo Cluster, such a M84 and M86. It is only 6.0″ x 1.5″ in size. However, it is thought to be 175,000 light years in size, making it larger than the Andromeda Galaxy.

My photo, which is enlarged from the original, includes 16 hours of imaging with  my 14-inch Planewave Reflector and FLI 16803 CCD camera. This includes five hours each via  R, G, B,  filters and 1 hour of H II. (I stopped the H II run when I realized I was not collecting any unique data.)

Larry McHenry: Observer from Pittsburgh

Galaxy NGC7184 is located in the fall zodiacal constellation of Aquarius – “The Water Bearer.”

The barred spiral is about 100 million light years distant, and is about 175,000 light-years in size. 

NGC 7184 was discovered on the night of October 28, 1783 by William Herschel using his 20-ft reflector, 

(with an  18.5-inch speculum-metal mirror), during his first full night of using his newly completed telescope in the back garden of his house, located in the small village of Datchet, about a mile from Windsor Castle. Herschel described the object as: “Faint, considerably large, much extended, brighter in the middle. Easily resolvable”. NGC 7184 was the first deep-sky object discovered by William Herschel using his system of ‘sweeping the sky’ and became the first object of Herschel’s Class-II – “Faint Nebulae” which consists mostly of galaxies.


On 09/20/2022, from Cherry Springs State Park at the Black Forest Star Party.  

Using an 8-inch SCT optical tube @ f/6.3 on a GEM mount, with a CMOS color camera and broadband filter, 180-second guided exposure, live-stacked for 30 minutes, image cropped. 

Using EAA techniques, the 11th mag NGC 7184 displays as an elongated, inclined mottled spiral with a bright oval core surrounded by a distinct circular ‘arm’ wrapping like a ring around the sides and foreground of the large core.