Friday Galaxy: NGC 7331

Jun 29 2007 Published by under Pretty Pictures

NGC 7331 is a spiral galaxy, probably not too dissimilar from our own (except that it lacks a bar), which is relatively nearby. (At a mere 49 million light-years, it's not in our own back yard, but it's just down the block.)

Image: Paul Mortfield and Dietmar Kupke/Flynn Haase/NOAO/AURA/NSF

Several years ago, the first time I thought Astronomy 253 ("Galactic Astrophysics"), I had an entire problem set entitled the "NGC 7331 problem set." In fact, this was a general problem set about the properties and dynamics of spiral galaxies, but I chose NGC 7331 as the example that was referenced in all of the problems.

Before I say the next thing, I want to say that the students in this class were a great bunch of students. One of them the next year would do research with me, and is now in graduate school at Colorado. I really enjoyed teaching this class, and really enjoyed working with that group of students.

So, disclaimers laid, so you don't read the rest of this the wrong way. I walked into the conference room that the particle physicists on my floor use for meetings and videoconferences; I've occasionally used it for the same purposes. That year, sometimes students would work together there. I walk into this room, and what do I see written on the whiteboard?

"I hate NGC 7331."

How sad.

8 responses so far

  • G Barnett says:

    Huh, is it just me, or does the central disc of that beaut look to be tilted about 10 deg off the plane of the outer portion?

  • tacitus says:

    I hate it too. You know what they say about first impressions.... 🙂

  • bigTom says:

    It certainly causes my brain to register that the spiral arm on the left is warped up in its outer regions. I don't know if its an optical illusion, or perhaps the result of a recent (ongoing?) gravitational interaction with another galaxy.
    So if we hate, NGC7331, does that mean we hate all/any aliens who reside within it. Discrimination/racism on a truly large scale!

  • Tony P says:

    You do realize the 7331 if flipped backwards would be 1337 or leetspeak for 'leet'.

  • mollishka says:

    How can someone hate something so pretty? Silly people.
    It does look like NGC 7331 has a warp. The Milky Way also has a warp, but I'm not sure if it would this large if viewed from the outside ... The Milky Way's warp is believed to be partially due to the Large Magellenic Cloud, so perhaps NGC 7331 has a small companion we can't see in this image.

  • Chris' Wills says:

    Well I think it is beautiful.
    Perhaps the person who didn't like it had problems with the mathematics associated with it?

  • Rob Knop says:

    They didn't really hate it. They were just struggling with the problem set because it was difficult.

  • Robert Lang says:

    Most spiral galaxies do not occupy a single plane in space.
    In fact, a lenticular or spiral galaxy that occupies a single plane is actually an unusual and exceptional object.

    Most spirals and lenticulars have warps, bends, changes in position angle, tilts of the disk plane, in some combination.

    NGC7331 is a good example of a galaxy which is obviously non-planar.