Stephan's Quintet is a group of five galaxies in the constellation Pegasus, with apparent magnitudes between 12.6 and 13.9; it was discovered in 1877 by the French astronomer Édouard Stephan at the Marseille Observatory (France).
In the black and white image here above (Wikipedia source) the names of the galaxies are detailed: the image has been rotated to make it correspond to my image.
The Stephan Quintet galaxies are not really connected to each other: according to redshift values measured, NGC 7320 could be 32 million light-years away from us, while the other four are at distances between 280 and 340 million light-years. NGC 7320 would therefore appear inside the Quintet only as a matter of perspective.
Finally, I was a little surprised to see such a “bright” galactic nebulosity all around this field of view!
Optic GSO RC12 Truss - Aperture 304mm, focal lenght 2432mm, f/8
Mount 10Micron GM2000 HPSII
Camera ZWO ASI 2600 MM Pro with filter wheel 7 positions
Filters Astrodon Gen2 E-Serie Tru-Balance 50mm unmounted LRGB
Guiding system ZWO OAG-L with guide camera ASI 174MM
Exposure details L 54x300" bin3 -15C
R 18x300" bin3 -15C
G 18x300" bin3 -15C
B 18x300" bin3 -15C
all gain 100
Total integration 9h
Acquisition Voyager, PHD2
Processing Pixinsight 1.8, Photoshop CS5, StarXTerminator, NoiseXTerminator, BlurXTerminator
Location Promiod (Aosta Valley, Italy), own remote observatory
Date 10/11 September 2023