One ring to rule them all

Galaxies can take many forms — elliptical blobs, swirling spiral arms, bulges, and discs are all known components of the wide range of galaxies we have observed using telescopes like the NASA/ESA Hubble Space Telescope. However, some of the more intriguing objects in the sky around us include ring galaxies like the one pictured above — Zw II 28.

Ring galaxies are mysterious objects. They are thought to form when one galaxy slices through the disc of another, larger, one — as galaxies are mostly empty space, this collision is not as aggressive or as destructive as one might imagine. The likelihood of two stars physically colliding is minimal, and it is instead the gravitational effects of the two galaxies that causes the disruption.

This disruption upsets the material in both galaxies, causing it to redistribute to form a dense central core, encircled by bright stars. All this commotion causes clouds of gas and dust to collapse and triggers new periods of intense star formation in the outer ring, which is thus full of hot, young, blue stars and regions that are actively giving rise to new stars.

The sparkling pink and purple loop of Zw II 28 is not a typical ring galaxy due to its lack of a visible central companion. For many years it was thought to be a lone circle on the sky, but observations using Hubble have shown that there may be a possible companion lurking just inside the ring, where the loop appears to double back on itself. The galaxy has a knotty, swirling ring structure, with some areas appearing much brighter than others.

A version of this image was entered into the Hubble’s Hidden Treasures image processing competition by contestant Judy Schmidt.

Credit:

ESA/Hubble & NASA
Acknowledgement: Judy Schmidt 

About the Image

Id:potw1310a
Type:Observation
Release date:11 March 2013, 10:00
Size:974 x 854 px

About the Object

Name:II Zw 28, VV 790b
Type:• Local Universe : Galaxy : Type : Ring
• X - Galaxies Images/Videos
Distance:z=0.028 (redshift)

Colours & filters

BandWavelengthTelescope
Infrared
I
815 nm Hubble Space Telescope
WFPC2
Optical
B
450 nm Hubble Space Telescope
WFPC2
Optical
S II
673 nm Hubble Space Telescope
WFPC2

Image Formats

Large JPEG
273.1 KB
Screensize JPEG
230.2 KB

Zoomable


Wallpapers

1024x768
280.5 KB
1280x1024
440.6 KB
1600x1200
595.5 KB
1920x1200
660.4 KB

Also see our