Shakhbazian 253: an extremely compact galaxy group

[Martin Meredith]

For all fans of compact galaxy groups, this one is, I think, a real gem. Shakhbazians tend to be somewhat fainter than Hickson groups but at the same time are typically more galaxy-rich. I spotted Shakhbazian 253 in CVn (at +37deg30', 13h 52 30) on the map and just had to look for it due to its interesting configuration and extreme compactness.

As the figure shows, this is a grouping of 13 galaxy candidates packed into roughly 2', all of which are in the range 16.4-18 in magnitude. The best estimate I could make of distance is around 0.95 billion LYs.  

By the time I got round to this group last night the wind was getting up and I couldn't manage to get more than a single 30s shot. Nevertheless, many of the members are evident. I star-hopped from nearby NGC 5341.

Here I've rotated the view to more or less match the map (N up) to show the members, most of which are in evidence with a little imagination. 

Its interesting to look at these groups also because they're on the margin of what galaxy catalogues such as LEDA show. For instance, galaxies 11 and 12 are not in the LEDA catalogue yet there is something visible in those locations which a longer exposure and stacking would clarify (not to mention peeking at the DSS image!). At the same time LEDA shows other galaxies which were not noted when Shakhbazian made her catalogue. This is one I'll return to.

cheers

Martin

[rharrison]

Fascinating, I might have to try and have a go at imaging this.

[michael.h.f.wilkinson]

Very interesting. You have definitely captured quite a few members of that group.

[nytecam]

Excellent Martin - I'll give it a go after the moon receeds:-)

[Martin Meredith]

Thanks everyone and for the likes too -- overwhelming! I'm glad others are interested in these faint groupings. I'd be interested in seeing some imaging attempts too. Will have another go myself tonight if the wind plays ball. There's another 376 Shakhbazians to take a look at too...

Martin

[Martin Meredith]

90% moon but windless tonight so I managed a stack of 12 x 30s for this object in which all 13 members are clearly visible. Interesting that where LEDA has a single mag 16.4 galaxy there are actually two (members 5 and 13) as Shakhbazian reported. Likewise, members 11 and 12 do indeed exist and have a galactic look about them.

In case anyone does find themselves in this area, there are a couple of remarkable interacting pairs close by, within a few degrees -- Arp 84 and VV 310 -- which I'll post in a separate thread.

Martin

[Paul81]

I'd never even heard of the Shakhbazian groups before reading this post! Great stuff!!

[Dragon Man]

I'd never even heard of the Shakhbazian groups before reading this post! Great stuff!!

Here ya go Paul, the collection: http://www.icg.port.ac.uk/~capozzid/Diego_Capozzi/Groups_SHK_Groups.html

Excellent shooting Martin    they are nicely captured.

[Pan Euro]

Great effort, well done.

[todd8137]

Well done to the both of you

Pat