Everything in the frame looks like one neighbourhood. Only two of these objects actually are.
The big spiral is NGC 7331, about 40 million light years away in Pegasus. It's often called a twin of our own galaxy, same size, same shape. If you could fly out and look back at the Milky Way, this is roughly what you'd see. Herschel found it in 1784. Messier missed it completely.
Those four little smudges crowding its edge? Not companions. They're background galaxies eight times further out. Astronomers call them the Deer Lick Group, the fleas on the deer.
Top right, that tight knot of five is Stephan's Quintet, the first compact galaxy group ever discovered, in 1877. Four of them are genuinely tearing each other apart 290 million light years away. The fifth is a fraud. It's only 40 million light years off and just happens to sit in the same line of sight.
Three hours, two targets, one 8-inch telescope from a backyard north of Bucharest.
The long version
NGC 7331 is one of the brightest galaxies William Herschel catalogued, in 1784, and one of the more conspicuous objects Messier never recorded. It's an unbarred spiral in Pegasus at roughly 40 million light years, frequently described as a structural analogue of the Milky Way. Its central bulge rotates counter to the disk, a sign of a disturbed history.
The four small galaxies apparently clustered along its eastern flank, NGC 7335, 7336, 7337 and 7340, are not associated with it at all. They lie some 300 million light years beyond, and the chance alignment earned the whole arrangement the name Deer Lick Group.
About half a degree to the northwest sits Stephan's Quintet, found by Édouard Stephan at Marseille in 1877 and the first compact galaxy group ever identified. NGC 7317, 7318A, 7318B and 7319 are a genuinely interacting system at roughly 290 million light years, with NGC 7318B ploughing into the group at around 800 km/s. NGC 7320 is a foreground interloper at about 40 million light years, a discordant redshift that fuelled decades of argument before it was settled as a line-of-sight coincidence.
Framing both in one field needed a camera rotation of 90°. They sit about 28 arcminutes apart, against a field of 1°00′ × 40′.
Acquisition
| Date | 16 September 2026, 21:15–23:50 EEST |
| Integration | 54 × 120 s at ISO 800, 1 h 48 m total |
| Calibration | 100 bias, 30 flats, matched darks |
Equipment
| Optics | GSO RC8 carbon, 203 mm, with TS 2″ Photoline 0.8× reducer, 1270 mm at f/6.3 |
| Camera | Canon EOS M50, no filter |
| Mount | HEQ5 Pro on PLL C82 pier, EQMOD |
| Guiding | ASI220MM Mini on TS 50 mm, pulse-guided, 4.13″/px |
| Control | N.I.N.A. 3.2.0.9001, PHD2 2.6.14 |
| Image scale | 0.604″/px, plate-solved at 1269.5 mm |
| Processing | Siril 1.4.4, calibration, registration, Winsorized sigma stacking, RBF background extraction, SPCC against Gaia DR3, generalised hyperbolic stretch |
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