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gvanhau
08-03-2014, 09:48 AM
As of WikipediA, the Antlia Cluster (or Abell S0636) is a cluster of galaxies located in the Hydra-Centaurus Supercluster. It is the third nearest to our Local Group after the Virgo Cluster and Fornax Cluster.
The Cluster is split into two groups, The Northern subgroup gravitating around NGC 3268, (near the centre on my image) and the Southern subgroup centered on NGC 3258 (at the bottom right of my image).

Here a larger image: http://www.flickr.com/photos/astro_gvanhau/12998231873/sizes/k/

Taken with my C8 at f/7.5 on my CGEM mount
Camera: QHY8L 21*10min (3.5h)
Guiding with Lodestar and self made OAG
Capture & guiding soft Maxim DL
Processing Soft PixInsigth.

Date: 28/02/2014 at Cajon Del Maipo (~50Km from Santiago de Chile).

Regards
Geert

ehgore1978
08-03-2014, 10:27 AM
great photo seriously looking at one of these cameras or an atik 314l love the clusters

cosmophoton
08-03-2014, 11:01 AM
Beautiful cluster of galaxies!

pvelez
08-03-2014, 11:12 AM
That is a great field - very nice image

Pete

madbadgalaxyman
08-03-2014, 11:43 AM
Nice image!

Antlia Cluster is probably somewhat closer than the Hydra Cluster of Galaxies and the Centaurus Cluster of Galaxies, based on the greater degree of morphological resolution of its galaxies, but last I checked (about a year ago), there was no reasonably accurate distance estimate for the Antlia Cluster of galaxies (say, at the +/-15 percent level of accuracy)

However, as is very often the case, the wikipedia entry was obviously written by someone who slavishly copies incorrect or out-of-date information.
In fact, closer than the Antlia cluster, there is also a third major cluster of galaxies, which is highly obscured because it is behind the Puppis Milky Way.

[[ Also, arguably, a nearby Poor Galaxy Cluster (or possibly a rich galaxy group) is the Ursa Major Cluster.]]

gvanhau
09-03-2014, 03:24 AM
Thanks Sctott, Pete, Luiz and Robert.

This is very interesting Robert. Can you mention a better info source than wikipedia in order to get more accurate info in the future?

Geert

strongmanmike
09-03-2014, 06:58 AM
Cool image Geert, I love galaxy clusters and this was one I wanted to do this season myself but may not get around to it now...so thanks for doing it for me :thumbsup:

Mike

IanP
09-03-2014, 02:24 PM
Beautiful part of the sky and very well photographed, well done .. :thumbsup:
The only thing I’d improve in the processing is the noise.
Maybe you can have a look at Harry’s ACDNR procedure and try to apply it to this spectacular image. :question:
http://www.harrysastroshed.com/ACDNR.html

madbadgalaxyman
10-03-2014, 10:08 PM
Unfortunately, there is no single source I know of ,which lists relatively accurate distances for the nearby clusters of galaxies.

A lot of the distance estimates are still made using inaccurate methods such as the Tully-Fisher Method or estimating the cluster distance from the mean recession velocity of a cluster
...... which tend to be only accurate at the 20 percent level. (this is sufficient for statistical work and for cosmological work)

So I make my own estimate of a cluster distance, by making a weighted mean of various published cluster distance estimates in the professional literature of astronomy, plus I also use my own observations of the size and resolution and surface brightness of the non-dwarf galaxies in a cluster. For instance, the first-ranked spiral galaxy within a cluster of galaxies is very often around Blue absolute magnitude -22 in luminosity, and its apparent angular size and its appearance in observations sometimes gives me a clue as to the distance of its host cluster.
(I don't know why spirals max out at a maximum luminosity of -22 !!)

R.B. Tully's "Extragalactic Distance Database" is a superb source of large numbers of individual distance estimates for many clusters of galaxies, but the individual distance estimates vary enormously in their accuracy:

http://edd.ifa.hawaii.edu/dfirst.php

The following papers provide a relatively accessible introduction to the clusters and the supergalactic structures found within the Hydra-Centaurus supercluster (but little about the great attractor, which is the subject of many papers written after these ones):

158417

158418