The Great Wall of Ara - NGC 6188

[SkyViking (Rolf)]

Hi All,

I finally got my full set of narrowband filters earlier this year (3nm Astrodon) and 'on the side' of my Antlia Cluster project I managed to gather enough data for my very first narrowband image: A 33 hour two panel high-resolution mosaic of the famous NGC 6188 in Ara.
Presented here are two versions: The blue/yellow Hubble palette image which highlights the structure of the nebula, and also a synthetic RGB image made from the narrowband data.

Image links:
Full resolution Hubble palette image (10Mb)
Full resolution RGB image (8Mb)
Full resolution Hubble palette crop

Large Hubble palette image
Large RGB image
Large Hubble palette crop

About the image:
NGC 6188 is a large emission nebula located some 4000 light years distant in the southern constellation Ara. This giant molecular cloud is being illuminated by the young star cluster NGC 6193 which in this image appears in the upper centre, almost as if suspended above a cloud of dense nebulosity which forms a great wall across the field of view.

The cluster belongs to the Ara OB1 association and is very young, not older than 3 million years, and contains some 30 stars. At the centre of the cluster lies an intensely bright pair of stars; the O-type giants HD 150135 and HD 150136. The latter is in fact itself an extremely close binary with a confirmed third component in an outer eccentric orbit of between 2950 and 5500 days. This triple star system is one of the most massive in our galaxy with the three components containing 64, 40 and 35 solar masses respectively.

The intense radiation from the massive stars is slowly eroding the surrounding gas and dust away, sculpting it into the striking forms seen in this image. Within these clouds new stars are currently being born and in some places have already begun to light up the nebulous clouds from within. The intricately shaped dust and gas provide for a stunning interplay of light and shadow throughout the area and the entire scene is littered with thousands of dimmer stars in a multitude of colours. Especially in the lower part of the image several long shadows can be seen cast by the glowing protruding dense portions of the nebula.

In many places giant clumps of material can be seen extending from the glowing clouds, reaching in the direction towards the NGC 6193 cluster. With the surrounding clouds slowly eroding away these denser structures will eventually emerge to resemble other more mature examples such as the famous "Pillars of Creation" in the Eagle Nebula.

This image is a mosaic of two fields, each constructed from exposures in three very narrow (3nm) wavelength bands corresponding to the emission profiles of ionised Hydrogen, Oxygen and Sulphur.

Image details:
Date: 13 nights, April to July 2015
Exposure: Ha:OIII:SII: 690:650:660 mins, total 33 hours 20 mins @ -30C
Telescope: Homebuilt 12.5" f/4 Serrurier Truss Newtonian
Camera: QSI 683wsg with Lodestar guider
Filters: Astrodon 3nm Ha, OIII, SII
Taken from my observatory in Auckland, New Zealand

I highly recommend browsing the full resolution images linked above. I was lucky to be imaging this magnificent nebula during a period with some really good seeing on most nights.
Hope you enjoy, and comments/critique is welcome as usual.

Regards,
Rolf

[Slawomir (Suavi)]

Fantastic images Rolf, I particularly like the blue/yellow version.

[gregbradley]

A magnificent 6188 Rolf. I like the first one the best. Very 3D and showing up the depth of objects very well.

Greg.

[Paul Haese]

I like the large versions. The Hubble palette images are my favourite. I really like the blue. My image of this year I did not get the blue that colour. Did 20 hours then. Good to see a nice deep image of the area. One of the best ones I have seen this year.

[RickS (Rick)]

Lovely images, Rolf. I prefer the Hubble Palette too but both are stunning.

Cheers,
Rick.

[Octane (Humayun)]

Sensational, Rolf.

One of my favourite objects!

H

[Camelopardalis (Dunk)]

Wow, what a cracker Rolf

[Peter Ward]

Very slick indeed....as usual

[TR (Terry)]

Rolf, I really like the nice subtle details that you have picked up along the ridge area excellent shot.

Terry

[Rod771 (Rod)]

Gee, that's realy good! Love the depth, fantastic!

I like the Hubble version and although I haven't shown my wife yet, she'll like the Synthetic RGB, "because its purple"

[Stevec35 (Steve)]

The usual top quality stuff Rolf! I think I marginally prefer the RGB. The 3D effect seems to stand out more to me.

Cheers

Steve

[Atmos (Colin)]

I think I prefer the first one (Hubble), so easy to get lost in all of the dust lanes
Fantastic shot as usual Rolf, you never do anything in half measures

[Placidus (Mike and Trish)]

A beautiful image, Rolf. Very three-dimensional. Lovely use of colour.

[strongmanmike (Michael)]

Great results Rolf, I like'em all as far as feedback goes, perhaps the RGB version is just a tad purple but meah, everything else is to like lots some excellent detail mate! Very enjoyable

Mike

[SkyViking (Rolf)]

Thank you all for your kind comments. Don't know how I missed replying back on this thread... apologies. I have been fairly absent lately due to moving house and other things. No obs at the new location yet either but am really looking forward to getting back in action later this year.
However, I did create some improved versions of these images recently, so links are now updated:

Updated image links:
Large Hubble palette image
Large RGB image
Large Hubble palette crop

[alpal]

Great image Rolf,
I hope you can get the new observatory site up & running soon.
Will it be a darker or better site?

cheers
Allan

[Paul Haese]

I think my preference is for the Hubble palette image. Your image has a very good composition. Not too wide and not too narrow.

[multiweb (Marc)]

Really nicely done Rolf. Always looking forward to your projects. I like the NB version best as well. I like how you've captured the shockwaves around that blue bright star in the middle and the details in the fine features of the wall pop up really well.