VLT Survey Telescope captures the Fornax Cluster
At the centre of this particular cluster, in the middle of the three bright fuzzy blobs on the left side of the image, is what is known as a cD galaxy -- a galactic cannibal. cD galaxies like this one, called NGC 1399, look similar to elliptical galaxies but are bigger and have extended, faint envelopes . This is because they have grown by swallowing smaller galaxies drawn by gravity towards the centre of the cluster .
Towards the bottom right of this image is the large barred spiral galaxy NGC 1365. This is a striking example of its type, the prominent bar passing through the central core of the galaxy, and the spiral arms emerging from the ends of the bar. In keeping with the nature of cluster galaxies, there is more to NGC 1365 than meets the eye. It is classified as a Seyfert Galaxy, with a bright active galactic nucleus also containing a supermassive black hole at its centre.
This spectacular image was taken by the VLT Survey Telescope at ESO's Paranal Observatoryin Chile. At 2.6 metres in diameter, the VST is by no means a large telescope by today's standards, but it has been designed specifically to conduct large-scale surveys of the sky. What sets it apart is its huge corrected field of view and 256-megapixel camera, called OmegaCAM, which was specially developed for surveying the sky. With this camera the VST can produce deep images of large areas of sky quickly, leaving the really big telescopes -- like ESO's Very Large Telescope VLT -- to explore the details of individual objects.
 The image captures only the central regions of the Fornax Cluster; it extends over a larger region of sky.
 The central galaxy is often the brightest galaxy in a cluster, but in this case the brightest galaxy, NGC 1316 , is situated at the edge of the cluster, just outside the area covered by this image. Also known as Fornax A, it is one of the most powerful sources of [radio waves] -- in the sky. The radio waves, which can be seen by specialised telescopes sensitive to this kind of radiation, emanate from two enormous lobes extending far into space either side of the visible galaxy. The energy that powers the radio emission comes from a supermassive black hole lurking at the centre of the galaxy which is emitting two opposing jets of [high-energy particles]. These jets produce the radio waves when they plough into the [rarefied gas] which occupies the space between galaxies in the cluster.
Source: ESO [April 13, 2016]