Space Warps Talk

Barred Ring Galaxy

  • gavinrider by gavinrider

    Can someone please explain the physics that apparently creates an almost circular bright disk while the rest of the galaxy structure appears to be viewed at an oblique angle, making the outer ring look like an ellipse?

    This looks more like a lens than some of the simulated lenses!

    It would be nice to see a Hubble image of this galaxy in high resolution.


  • Tom_Collett by Tom_Collett scientist

    This galaxy is actually face on - but it has a bar going across the middle of it. The bar is a resonant feature that can form because the disk of the galaxy contains lots of individual stars. It's a similar effect to how spiral arms form (why don't spirals just look like dinner plates). As the bar spins round the centre of the galaxy it usually generates lots of star formation at its ends - hence the blue ring.


  • gavinrider by gavinrider in response to Tom Collett's comment.

    So why is the outer ring of stars elliptical if the galaxy is face-on?


  • Capella05 by Capella05 moderator

    Hi gavinrider 😃

    The shape of the outer ring has nothing to do with the galaxy being face on - face on just means we are viewing the galaxy as if it was straight ahead i.e we are not viewing it at an angle. Not being able to see the entire galaxy the outer ring may not be a ring at all, but dislocated spiral arms (this is the term we used over @galaxyzoo - probably very unscientific!) that has settled into that pattern.