NGC 7331 ~ Deer Lick Group
Optics:   Ritchey–Chrétien 20" F/8.2 (4166mm FL) Processing:   PixInsight, Photoshop
Camera:   SBIG STXL-11000 with Adaptive Optics Date:   2014 Á 2020
11 Megapixel (4008 x 2672 16-bit sensor) Location:   Columbus, Texas
Exposure:   LRGB = 1600:160:160:180 minutes Imager:   Kent E. Biggs
NGC 7331 is the flagship galaxy in a group of visually associated galaxies call the NGC 7331 group or “The Deer Lick Group.” The name “Deer Lick” is attributed to author, photographer and amateur astronomer, Tomm Lorenzin who named it such in honor of an extremely fine night of viewing this group of galaxies at Deer Lick Gap in the North Carolina mountains. NGC 7331, also cataloged as Caldwell 30, is about 40 million light-years away in the direction of the constellation Pegasus, the white winged horse of Greek mythology.

It is only a coincidence that visually places NGC 7331 with the other member galaxies of this group including NGC 7335, 7336, 7337, and 7340. All of these visually smaller galaxies are nearly 8 times further way placing them somewhere between 290 to 370 million light-years! This makes all the galaxies comparable in size to NGC 7331 even though they appear smaller. Some have compared the visually larger NGC 7331 to our own Milky Way galaxy in both mass and appearance. However, while it may indeed have similar mass and star count, NGC 7331 is an unbarred spiral galaxy, whereas our Milky Way is a barred spiral galaxy making our galaxy more similar to NGC 7337 in this image (above and left of center of NGC 7331 as annotated in the image above). NGC 7336 in the image is also a barred spiral, however the other galaxies in the group appear to all be unbarred spiral or elliptical galaxies. All of these galaxies including NGC 7331 contain from 100 to 300 billion or more stars.

William Herschel discovered NGC 7331 in 1784. While NGC 7331 is likely circular or slightly elliptical in shape, it is relatively flat and, like a dinner plate tilted toward us, nearly edge-on from our point of view. Nevertheless, its spectacular spiral arms of mostly white and bluish white stars are beautiful both visually and photographically. What makes NGC 7331 a bit unusual is that in most galaxies the central nucleus of stars and surrounding disk rotates with the rest of the galaxy, however measurements of spectra shifts the central region of NGC 7331, show it to be rotating in the opposite direction compared to the outer spiral arms. NGC 7331 is home to several supernovae recorded throughout the 1900’s and early 2000’s.

Note in the insets above, several of the galaxies have been enlarged to see more detail. Click on the image to see a full screen and zoomable image. In the lower left portion of the image is annotated 3 very distant galaxies much further than the 40 million light years to NGC 7331, and even much further than the 300 million or so light years to the other background galaxies visible here.

The below image shows the same NGC 7331 group but without stars. Every star visible in the image above is in our own Milky Way galaxy, but when they are removed using AI algorithms, hundreds of other very faint galaxies become more visible, some as far as a billion light-years way or further! This is nearly 10 percent to the edge of the observable universe, that part of the universe that expands away from us at sub-light speeds. According to physics, nothing can travel faster than light, but because of the way the universe seems to expand proportionally to the distance between objects, about 99.9% of objects in our universe are now traveling away from us at speeds faster than light and therefore will never be observable by humans. In other words, the universe is about 1000 times bigger than we can every see!

NGC 7331 without Stars!


The image below shows a zoomed in view of the NGC 7331 group.


The image below shows a brightened view of the NGC 7331 group Note the additional dust and gas visisble, some of it between galaxies and others in our own galaxy.

NGC 7331 Zoomed In

The images below are older images processed with my Generaion 0 and Generation 1 processing techniques. The bottom image was taken with the previous generation 3.4 megapixel camera.
NGC 7331 ~ The Milky Way's Twin?
Optics: RC Optical System 20" F/8.2 (4165.6 mm Focal Length) Date: June-August 2020
Camera: SBIG STXL-11000 with AO-X Adaptive Optics Location: Columbus, Texas
Exposure: LRGB = 820:80:80:100 minutes Imager: Kent E. Biggs
NGC 7331 is an unbarred spiral galaxy about 40 million light years away in the direction of the constellation Pegasus, the winged horse of ancient Greek mythology. The words "in the direction of" is used here, since no astronomical object is ever really "in" a constellation. Constellations are made up collections of stars by humans that are as fleeting as cloud shapes on an astronomical scale. NGC 7331 appears to be surrounded by a group of galaxies, but all of the other galaxies highlighted in this image are much much further away at 300 and 400 million light years distant. Hovering over the image will show the names of the other brighter galaxies in this image. Until the early 2000s, it was believed that NGC 7331 was very similar to our own Milky Way galaxy and hence called its twin. However, discoveries have proven that our galaxy, although similar in size and number of stars, is actually a barred spiral galaxy that has a bar structure running through the center. NGC 7331 cleary has no bar and is therefore different from our own galaxy. One interesting observation about NGC 7331 is that if you look closely enough you will see that the center core of the galaxy is not perfectly centered, as it favors the left side in this image. Furthermore, it appears slightly inclined compared to the disk of the entire galaxy. Amazing enough, this central disk is actually rotating in the opposite direction of the galaxy, a mystery among many others about the nature of galaxy formation and their behaviors.

NGC 7331 - Earlier Imaging and Gen1 Processing.
Optics: RC Optical System 20" F/8.2 (4165.6 mm Focal Length) Date: October 2010
Camera: SBIG ST10XME with Adaptive Optics Location: Columbus, Texas
Exposure: LRGB = 400:120:80:120 minutes Imager: Kent E. Biggs
NGC 7331 is one of the most impressive spiral galaxies in the sky. It is the brightest galaxy not to be included in the famous Messier catalog of 100+ objects familiar to most amateurs. Some refer to this galaxy as our own Milky Way Galaxy's twin due to its appearance, but recent research suggests that our galaxy is actually a barred spiral. NGC 7331 is often called the Deer Lick Group named by Tomm Lorenzin coinciding with his best view of the group during a trip to the Deer Lick Gap in the Smokey Mountains. At 40-50 million light years, NGC 7331 is moving away from us at over 500 miles per second and is slightly larger than our own galaxy. The "smaller" galaxies in the image are far in the distant and probably of similar size and mass to this galaxy. The stats for this galaxy are RA: 22h 37m 04.5s, Dec: +34° 25' 00", Mag: 9.4 (V), Size: 14.5'x3.7', Class: SA(s)b.