Mysterious Ring Galaxy With Unique Shape Imaged by Hubble [Photo]

There are not so many different forms galaxies can take — everyone knows the most common spiral galaxies, and there are also the older specimen that evolved into disks, often elliptical. Blobs and bulges are also known components of the range of galaxies we have observed using telescopes like the NASA/ESA Hubble Space Telescope. A rare variant in the sky around us includes ring galaxies like the one pictured here, bearing the designation Zw II 28.

Ring galaxies are mysterious objects and are believed to form only when one galaxy slices in the right way through the disk of another, larger, one. Because galaxies are mostly empty space, with light years between the single stars, such a collision is not as spectacular and 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 cause the disruption.

This kind of disruption upsets the material in both galaxies, and usually redistributes it in such a way that a dense galactic core is formed, 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 full of hot, young, blue stars and regions that are actively giving rise to new stars.

Thats why the ring galaxy Zw II 28 is not normal, the galactic core is completly missing and instead it is a true and pure ring, a sparkling pink and purple loop. 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 knot-like, swirling ring structure, with some areas appearing much brighter than others.