RAS: Galaxy-Sized Peanuts?

[bystander]

Astronomers use new imaging software to detect double ‘peanut shell’ galaxy
Royal Astronomical Society | 2016 May 06

[img3="The galaxy NGC 128 is viewed with its disc in an edge-on orientation in this SDSS false-colour image. A (peanut shell)-shaped bulge can be seen around the thin disc. Its inner peanut shell is 5 times smaller. Credit: Sloan Digital Sky Survey / B.Ciambur (Swinburne University of Technology) / NASA / ESA"]http://www.ras.org.uk/images/stories/pr ... gc-128.png[/img3][hr][/hr]

Astronomers at Swinburne University of Technology, Melbourne, have discovered an unusually shaped structure in two nearby disc galaxies. The Swinburne team recently developed new imaging software, making it possible to observe the double “peanut shell shape” formed by the distribution of stars bulging from the centres of these galaxies. ...

Astronomers at Swinburne University of Technology, Melbourne, have discovered an unusually shaped structure in two nearby disc galaxies. The Swinburne team recently developed new imaging software, making it possible to observe the double “peanut shell shape” formed by the distribution of stars bulging from the centres of these galaxies. ...

Although the ‘bulges’ of both galaxies were already known to display a single peanut shell pattern, astronomers had never before observed the fainter second structure in any galaxy. ...

Astronomers believe that peanut shaped bulges are linked to the bar-shaped distribution of stars that is observed across the centres of many rotating galaxy discs. Each of the two galaxies observed contain two such bars, and it is thought that one way the peanut shaped structures may arise is when these bars of stars bend above and below the galaxy’s central disc. ...

The study may also shed new light on the peanut-shaped bulge of our own Milky Way galaxy, which some astronomers suspect contains two stellar bars. ...

Double 'peanut shell-shaped' feature of a galaxy discovered
Swinburne University of Technology | 2016 May 06

Quantifying the (X/Peanut)-Shaped Structure in Edge-on Disc Galaxies:
Length, Strength, and Nested Peanuts - Bogdan C. Ciambur, Alister W. Graham

• Monthly Notices of the RAS 459/2/1276 (2016 Jun 21) DOI: 10.1093/mnras/stw759
  arXiv.org > astro-ph > arXiv:1603.00019 > 29 Feb 2016 (v1), 04 Apr 2016 (v2)

[Ann]

Astronomers use new imaging software to detect double ‘peanut shell’ galaxy
Royal Astronomical Society | 2016 May 06

[img3="The galaxy NGC 128 is viewed with its disc in an edge-on orientation in this SDSS false-colour image. A (peanut shell)-shaped bulge can be seen around the thin disc. Its inner peanut shell is 5 times smaller. Credit: Sloan Digital Sky Survey / B.Ciambur (Swinburne University of Technology) / NASA / ESA"]http://www.ras.org.uk/images/stories/pr ... gc-128.png[/img3][hr][/hr]

Astronomers at Swinburne University of Technology, Melbourne, have discovered an unusually shaped structure in two nearby disc galaxies. The Swinburne team recently developed new imaging software, making it possible to observe the double “peanut shell shape” formed by the distribution of stars bulging from the centres of these galaxies. ...

Astronomers at Swinburne University of Technology, Melbourne, have discovered an unusually shaped structure in two nearby disc galaxies. The Swinburne team recently developed new imaging software, making it possible to observe the double “peanut shell shape” formed by the distribution of stars bulging from the centres of these galaxies. ...

Although the ‘bulges’ of both galaxies were already known to display a single peanut shell pattern, astronomers had never before observed the fainter second structure in any galaxy. ...

Astronomers believe that peanut shaped bulges are linked to the bar-shaped distribution of stars that is observed across the centres of many rotating galaxy discs. Each of the two galaxies observed contain two such bars, and it is thought that one way the peanut shaped structures may arise is when these bars of stars bend above and below the galaxy’s central disc. ...

The study may also shed new light on the peanut-shaped bulge of our own Milky Way galaxy, which some astronomers suspect contains two stellar bars. ...

Double 'peanut shell-shaped' feature of a galaxy discovered
Swinburne University of Technology | 2016 May 06

Quantifying the (X/Peanut)-Shaped Structure in Edge-on Disc Galaxies:
Length, Strength, and Nested Peanuts - Bogdan C. Ciambur, Alister W. Graham

• Monthly Notices of the RAS 459/2/1276 (2016 Jun 21) DOI: 10.1093/mnras/stw759
  arXiv.org > astro-ph > arXiv:1603.00019 > 29 Feb 2016 (v1), 04 Apr 2016 (v2)

Click to view full size image

NGC 128 and friends. Photo: SDSS.

NGC 128 is a very yellow, non-starforming galaxy, as can be seen in the SDSS/galaxyzooforum image at left. It looks pretty large, too. According to Principal Galaxy Catalog, it is more than twice as luminous as the Milky Way, and probably a lot more massive.

NGC 936, a barred lenticular galaxy.
Photo: SDSS.

To me, NGC 128 looks like just the sort of galaxy that might be expected to have a peanut-shaped bulge. Note that you can see the peanut shape in the SDSS visual image, too.

From a face-on perspective, NGC 128 might resemble NGC 936. However, NGC 128 appears to be a much larger galaxy than NGC 936, and my guess is that it has a longer bar, as well as a more pronounced peanut-shaped bulge.

Ann

[geckzilla]

I don't like the calling it a "peanut" shape. I call it an X.