Terzan 9 – the countdown continues…

[Dennis]

Hello,

Here is an image of Terzan 9, one of the 11 Globular Clusters discovered in 1968 by Agop Terzan in France whilst doing infrared work. Although I didn’t consciously set out to record the entire set of these esoteric GC’s, I have ended up with 3 of them; Terzan’s 11, 10 and 9. Weather and enthusiasm permitting, I might continue until I grab the complete collection, provided of course, that Gerald continues to extend the loan of his SBIG ST2000 and CFW10!

Imaging these faint objects via a series of quick raids into Sagittarius and Scorpius has kept me ticking over during a somewhat unproductive 2010, mainly due to unfavourable weather in Brisbane and my somewhat erratic enthusiasm. This image of Terzan 9 was captured beneath some quite soft, hazy skies which eventually turned into fog hence the clarity has suffered.

Terzan 9 details:
SkyTools Pro 3 provides the following details about Terzan 9:
R.A.: 18h01m39.0s Dec.: -26°50'24" (2000) in Sagittarius
Magnitude: 16.00, Size: 12"

Attached files:
Main image:
Full 1600x1200 frame, down sampled to 1024x768.
Original image scale 0.82 arcsec/pixel, FOV approx 22' x 16'.

DSS Image:
STScI(US) Second Generation DSS Red, downloaded via SkyTools Pro 3.

Imaging Details:
Brisbane, Qld, Australia
12th July, 2010.
Tak Mewlon 180 F12 with x0.8 Reducer at an efl of 1728mm (F9.6).
ST2000 and CFW10
Luminance: 3 x 15 minutes.
RGB 1 x 10 minute each.

Terzan globulars:
Some background details on the Terzan globulars can be found here.
http://natkobajic.netfirms.com/listTERZAN.html
http://astronomy-mall.com/Adventures...ce/obscure.htm

Cheers

Dennis

[h0ughy (David)]

EXCELLENT!! (said in Mr burns Voice)

[[1ponders] (Paul)]

Top Shelf Dennis, top shelf.

I reeeally want to pick your brains at astrofest my friend.

[jase (Jason)]

Remarkable Dennis. I had heard of the Terzan GC's but had not contemplated them as visual targets for imaging. Given their magnitudes and small angular size, its quite a challenge you've taken up. Inspiring work.

[multiweb (Marc)]

Top stuff Dennis! Great read too. You always come up with interesting projects.

[Dennis]

Thanks Dave – I could probably do one Terzan a night if I had an observatory like yours, weather dependant off course!

Originally Posted by h0ughy

EXCELLENT!! (said in Mr burns Voice)

Thanks Paul – that will take all of 5 minutes!

Originally Posted by [1ponders]

Top Shelf Dennis, top shelf.
I reeeally want to pick your brains at astrofest my friend.

Thanks Jase – I appreciate your comments. Projects like this are a nice way of gradually easing into the stiff climb up the LRGB Mountain!

Originally Posted by jase

Remarkable Dennis. I had heard of the Terzan GC's but had not contemplated them as visual targets for imaging. Given their magnitudes and small angular size, its quite a challenge you've taken up. Inspiring work.

Thanks Marc – it was Rolf (SkyViking) who started the ball rolling with his amazing captures of Terzan 5 and UKS-1.

Originally Posted by multiweb

Top stuff Dennis! Great read too. You always come up with interesting projects.

Cheers

Dennis

[SkyViking (Rolf)]

I see you are at it again Dennis This is a fabulous shot of Terzan 9, I really like the colours and overall the image is beautifully processed and very smooth! I think this is your best Terzan so far
It's great to see the reddish colour of the cluster, revealing just how much obscuring dust that lies in front.

I wonder about the size - 12"? When I searched for Terzan 5 I noticed that it too was listed with a miniscule size in Starry Night - I reckon they are all quite a bit larger than that. They are not tiny globulars, but merely obscured by interstellar dust and appear much larger than 12" on images.

Hopefully you can manage to collect them all, that would be quite an achievement. Thanks for sharing!

[Alchemy (Clive)]

An interesting challenge. Nicely exposed and processed too.

[Hagar (Doug)]

Great shot Dennis, a tiny little target to capture.
Well done.

[Dennis]

Thanks Rolf! Yes the object certainly looks a lot larger than 12” and from the various resources I have looked at, there seems to be some significant variations in the reported sizes of these objects. Maybe some sources are reporting the central condensation of stars whilst others include the obscuring red stuff which spans arc minutes rather than arc secs.

It should be interesting to image a couple of these from the darker skies of the Qld Astrofest from Aug 6th to 15th.

Originally Posted by SkyViking

It's great to see the reddish colour of the cluster, revealing just how much obscuring dust that lies in front.

I wonder about the size - 12"? When I searched for Terzan 5 I noticed that it too was listed with a miniscule size in Starry Night - I reckon they are all quite a bit larger than that. They are not tiny globulars, but merely obscured by interstellar dust and appear much larger than 12" on images.

Thank you Clive & Doug – I appreciate you stopping by and having a look. Although these are classed as “difficult” objects, I find the processing is much more straightforward than the LRGB stuff you guys are producing with the larger chips and wider shots. I don’t have to deal with gradients, nebulosity, etc.

Originally Posted by Alchemy

An interesting challenge. Nicely exposed and processed too.

Originally Posted by Hagar

Great shot Dennis, a tiny little target to capture.
Well done.

Cheers

Dennis

[JD2439975 (Justin)]

Another notch on the ol' tripod leg Dennis, excellent capture.