NGC 7331 is one of the finest galaxies in the northern sky not cataloged by Messier—yet it easily rivals many of them in both brightness and beauty. Located in the constellation Pegasus, this spiral galaxy lies about 40 million light-years away and spans nearly the same size as our Milky Way. What makes it so enticing is its striking appearance: it’s tilted at an angle, offering a lovely edge-on perspective with a slightly curved, elongated disk and a bright, concentrated core.
At magnitude 9.5, NGC 7331 is visible in small to medium telescopes, especially under dark skies. In smaller instruments, it appears as a soft, spindle-shaped glow with a brighter center, while larger apertures begin to reveal its dust lane, hinting at its spiral structure. The galaxy floats in a relatively uncrowded part of the sky, giving it a solitary majesty that feels both distant and grand.
But there’s more -- four much smaller and dimmer galaxies. Together they are sometimes called the “Deer Lick Group” with the smaller ones called the 'fleas' (though they’re actually much farther away in the background). And just a half-degree to the south is another group of galaxies known as Stephan's Quintet. To view these dim galaxies, it helps to use a large telescope under very dark skies (bortle 1-2).
Best viewed from late summer through autumn, NGC 7331 is well-placed during evening hours from August through December. Its brilliance, structure, and elegant tilt make it a favorite among seasoned observers—and a fantastic galaxy for anyone ready to move beyond the Messier list.
C30 (NGC 7331)
Rating: 🟢 Solid Catch
Level: 🟢 Moderate
How:
When: Aug - Dec
🌟 Moderately Easy to Find With a magnitude of 9.5, NGC 7331 is bright enough to be spotted in small telescopes under dark skies and becomes increasingly rewarding in larger instruments. Located just north of the bright star Eta Pegasi (also known as Matar), it’s easy to locate with a star-hop.
🌟 A Striking Edge-On Spiral Galaxy NGC 7331 is tilted at an angle that gives observers a nearly edge-on view of its disk. This orientation creates a striking visual: a slender, elongated galaxy with a prominent central bulge and hints of a dust lane cutting across its soft glow. Even in modest telescopes, this shape is apparent, giving the galaxy a strong sense of structure and depth.
🌟 A Stand-In for the Milky Way Astronomers often call NGC 7331 a Milky Way analog because of its size, structure, and star population. Observing it offers a kind of poetic experience—it’s a chance to see what our own galaxy might look like from afar. For stargazers, that makes it more than just a galaxy; it becomes a mirror to our place in the universe.
🌟 Surrounded by a Faint Galactic Ensemble Larger telescopes reveal that NGC 7331 isn’t entirely alone. It’s visually accompanied by a group of much fainter galaxies known as the “Deer Lick Group.” These background galaxies appear to cluster just to the side of NGC 7331, adding a sense of scale and context to the scene. Spotting them is a fun challenge that transforms this into a multi-galaxy field.
🌟 Ideal for Autumn Viewing NGC 7331 is perfectly placed for observing during fall evenings. From August through November, it climbs high in the northern sky, reaching culmination at a comfortable hour. Its location in Pegasus also puts it in close proximity to several other fascinating targets, including the famous Stephan’s Quintet, making this area of sky especially rich for galaxy hunters.
🌟 A Rewarding Target for Astrophotographers For those with imaging gear, NGC 7331 is a rewarding subject. Its structure, the contrasting brightness of its core and disk, and the surrounding galaxies make for a visually rich and balanced composition. Even modest exposures can bring out the galaxy’s shape, while longer integrations reveal faint tidal features and surrounding companions.
Spiral galaxy: a galaxy with a flat, rotating disk of stars, gas, and dust, featuring winding spiral arms and a central bulge.
C30 (NGC 7331)
Like so many great targets in Autumn, to find NGC 7331, we start with the Great Square of Pegasus.
Find the Great Square of Pegasus which is often to the east in Autumn evenings by locating its four main stars that form the corners of the square. Find Scheat (+2.47) and then the two stars that form the lower-front leg of the horse, Matar (also known as Eta Pegasi) (+2.94) and much dimmer Pi Pegasi (+4.28). Using a telescope finder, point to Matar.
Using a low-powered eyepiece, slowly hop from Matar in the direction of Pi Pegasi. If you can't see Pi Pegasi naked-eye, simply go in the same direction as Matar is from Scheat. At the halfway point, look for three relatively bright stars that form a triangle, HR 213340 (+6.59), HR 8555 (+5.98), and 38 Pegasi (+5.63). Now, slowly hop 2.5° from 38 Pegasi to NGC 7331 by continuing in the same direction while watching for a faint, elongated smudge with a brighter central bulge. Once you’re there, increase the magnification to reveal the galaxy’s slender, tilted shape more clearly.
Bonus Targets: if you are viewing under very dark skies and with a large telescope, look on the east side of NGC 7331 for four small and very dim galaxies: NGC 7335 (+13.38), NGC 7336 (+15.64), NGC 7337 (+15.64) and NGC 7740 (+14.64). They are all within a quarter-degree of NGC 7331 and should fit in the same field of view of a low to medium-powered eyepiece. For an additional challenge, look 0.5° to the south for the somewhat brighter galaxies of Stephan's Quartet. Good luck!
C30 (NGC 7331)
✅ Use a Medium Telescope or Larger With a magnitude around +9.5, NGC 7331 may appear only as a soft, elongated glow in a small telescope. With increasing aperture, it becomes a much more impressive sight revealing more details.
✅ Observe Under Dark Skies NGC 7331 benefits greatly from Bortle 1–3 skies. Light pollution washes out its fainter disk and background galaxies. Under dark conditions, its central bulge brightens and its full structure becomes much more apparent.
✅ Let Your Eyes Adjust Fully Give your eyes 20–30 minutes to adapt to the dark before attempting to observe faint structure. This will make the galaxy’s spindle shape and subtle glow easier to detect, especially in smaller scopes.
✅ Try Averted Vision Looking slightly off to the side helps reveal the galaxy’s extended disk and outer halo. Averted vision is especially helpful for teasing out faint edges and spotting members of the Deer Lick Group nearby.
✅ Explore the Entire Field Once you’ve centered NGC 7331, use higher power or longer exposure to look for nearby faint galaxies—part of the visual “Deer Lick Group.” These companions add depth to the view and make the observation more rewarding.
C30 (NGC 7331)
❌ Naked Eye
NGC 7331 is not visible to the naked eye. With a magnitude around 9.5, it lies far below the threshold of unaided visibility, even under the darkest skies.
❌ Binoculars
In binoculars, even large 15×70 models, NGC 7331 is extremely difficult to detect. Under very dark skies, it may appear as a barely perceptible smudge with careful sweeping and averted vision, but most stargazers will find it elusive.
⚠️ Small Telescope
With a small telescope, such as a 3- to 4-inch refractor or reflector, NGC 7331 begins to show itself as a soft, elongated glow. The galaxy appears spindle-shaped with a brighter core and a hint of structure. Under dark skies, it’s an easy catch in this aperture range, especially at moderate magnification. However, finer details like the dust lane or faint companion galaxies remain out of reach.
✅ Medium Telescope
In a medium telescope of 6 to 8 inches, NGC 7331 becomes a much more impressive sight. The central bulge is bright and well-defined, and the elongated disk stretches gracefully across the field of view. Under steady, dark skies, careful observation can reveal a subtle darkening along one edge—an indication of the galaxy’s dust lane. The Deer Lick Group of background galaxies may begin to emerge at higher magnification, adding depth and interest to the field.
✅ Large Telescope
A large telescope of 10 inches or more transforms the view. The galaxy’s bulge and disk become sharply contrasted, and the dust lane may appear as a distinct shadow slicing through the central light. Faint outer regions and tidal extensions are detectable under excellent skies, and several of the background galaxies in the Deer Lick Group become visible. In this aperture range, NGC 7331 is not just a galaxy—it becomes a dynamic scene rich with structure and cosmic scale.
C30 (NGC 7331)
NGC 7331 is best viewed under dark skies, where its tilted spiral structure and nearby galaxies become vivid and rewarding. In light-polluted skies, it fades into a dim blur, retaining only its bright core.
🟣 In Bortle 1–2 skies, NGC 7331 is striking and well-defined. Its bright core and elongated disk stand out clearly against a dark, transparent background. The dust lane is subtle but detectable, and faint companion galaxies nearby begin to emerge with careful observation.
🔵 Under Bortle 3–4 skies, the galaxy remains prominent and rewarding. The central bulge is bright, and the disk is still visible, though lower contrast makes faint features like the dust lane more difficult. The surrounding field loses some depth but still offers a satisfying view.
🟡 In Bortle 5–6 conditions, NGC 7331 becomes more subdued. The galaxy is still visible, but its disk fades into the skyglow, and the dust lane is nearly impossible to detect. The surrounding galaxies disappear, and only the bright core remains prominent.
🔴 Under Bortle 7+ skies, light pollution overwhelms the galaxy’s faint outer regions. NGC 7331 may be glimpsed as a faint, fuzzy patch with a brighter center, but its structure is mostly lost. The beauty and detail it offers under dark skies are significantly diminished.
C30 (NGC 7331)
DSOs within 48° or 2 outstretched hands at arm's length
C30 (NGC 7331) - The Milky Way’s Distant Twin
Find the Great Square of Pegasus which is often to the east in Autumn evenings by locating its four main stars that form the corners of the square. Find Scheat (+2.47) and then the two stars that form the lower-front leg of the horse, Matar (also known as Eta Pegasi) (+2.94) and much dimmer Pi Pegasi (+4.28). Using a telescope finder, point to Matar.
Using a low-powered eyepiece, slowly hop from Matar in the direction of Pi Pegasi. If you can't see Pi Pegasi naked-eye, simply go in the same direction as Matar is from Scheat. At the halfway point, look for three relatively bright stars that form a triangle, HR 213340 (+6.59), HR 8555 (+5.98), and 38 Pegasi (+5.63). Now, slowly hop 2.5° from 38 Pegasi to NGC 7331 by continuing in the same direction while watching for a faint, elongated smudge with a brighter central bulge. Once you’re there, increase the magnification to reveal the galaxy’s slender, tilted shape more clearly.
