Centaurus A Galaxy with Ha & Oiii jets

[Dave882]

An early start on the Southern galaxy season - with a run of clear nights under the full moon last week, I found myself hunting for something new - and of course I ended up imaging NGC5128 again for about the 7th time... but after inspiration from some wonderful results from other astronomers, I really wanted to have a crack at revealing the Ha jet emanating from this intriguing beauty. Armed with the IDAS NBZ dual band Ha/Oiii filter and with the c14 in Hyperstar mode (f1.9) I managed to pull in just on 10hrs of data in the wee hours over 3 nights.

Interestingly, even though there are many images and info about the Ha jets, it was actually some corresponding Oiii jets that were revealed fairly early on in the data, and it was the Ha that really needed some coaxing. I started with 60sec subs, then 120sec, and finally a night of 300sec subs until I was starting to see the Ha in the stacked data. Of course this destroyed the view of the actual galaxy, so I managed to pull some c14 (2hrs @ 2700mm fl) data from last year in RGB and layer this in using GIMP to improve the overall result. Apologies in advance for the terrible star colours the the NBZ delivers.

As the NBZ filter has 12nm bands, and under heavy light pollution + full moon the noise was still extremely challenging to deal with, especially when trying to pull out such faint detail. I was quite sure I was seeing some Ha on the southern side of the galaxy, but only found references to this in extremely long integration shots with much better gear than my own so put this down to artefacts until I can manage another 50 or so hrs integration to verify.

Here's the pic. (https://1drv.ms/u/s!ArpSiLT3VkGHiPM99-qHdCjIfAftxA?e=4tsOb1)

The details:
c14 Hyperstar f1.9 IDAS NBZ - 10hrs at 60, 120, 300sec subs
c14 f7 no filter - 2hrs of 120sec subs
asi2600mc gain100, -10degrees
eq8 mount
ASIAIR Pro acquisition
APP stacking
GIMP / LR processing

Thanks for looking!

[Startrek]

Dave,
Great effort under moon lit skies on this popular target
Excellent detail and colours
Well done indeed !!!
I’ve picked up the red/ pinks and blues on this Galaxy but only down south under dark skies at bortle 3/4
In Sydney I can only image galaxies during the new moon period (next 2 weeks) as the heavy LP and general ambient artificial light from neighbours kills the detail and colour, plus I don’t t have the reach. My new Carbon fibre 8” is due to arrive from Germany in a week or two , so it gives me more capability imaging galaxies in Sydney for the future ( as well as everything else)
There’s quite a few galaxies around but still low on the horizon up to 25 to 30 deg max
April to September is my favourite time of the year for imaging, so many options

Cheers
Martin

[EpickCrom]

Hi David.

Fantastic results! Your image is stunning.

[Dave882]

Thanks guys much appreciated.

Martin- after experiencing a couple of nights in dark(ish) sky I’m finding the LP more and more depressing. Fortunately with narrowband filters it make it a bit easier, but I love my galaxies :shrug: I can generally pick up nice blue/pink in the galaxies but the deeper detail is extremely challenging. I’ve added a crop image to the post which shows the Ha and Oiii (deeper red and greenish) jets coming out at 10 o’clock. While the galaxy itself is visible through the eyepiece, these jets were only just coming into view after 10hrs integration. I can’t wait to see what you can do this galaxy season with your 10” in B4 sky!

[AdamJL]

Awesome work, David!

[strongmanmike]

Cool project David and good use of the available sky time, well done. If you could be bothered, some more Ha should reveal the main red jet can be traced even further out from Cen A :thumbsup:

Mike

[Dave882]

Thanks Adam
Mike, more integration would certainly help but I think I’m so close to the noise floor on the Ha jet it’d really only be possible to reveal more from a darker site or with much narrower bandpass filters… and I’ve also really gotta up my post processing game lol so much to improve on. I’m certain I’ll come back to this one again

[kosborn]

Great image. I particularly like the OIII contribution in the jet.


Kevin

[Dave882]

Thanks Kevin- yes it was a pleasant surprise and only identified due to using dual-band filter to pick up the Ha. It is actually much brighter and more prominent than the Ha jets…

[Addos]

v nice dave! great job picking up that fainter detail! background looks nice and consistent too, well done!

[Dave882]

Thanks Adam yeah that was quite challenging actually- especially combining the 2x fl data sets causing all sorts of gradient/star issues. But yeah the main goal was to see if I could expose those faint jets and was really pleased to do that
Cheers mate

[Paul Haese]

Well done Dave. I can see the jet in your image. It is a really faint one, having imaged it myself I know it can be troublesome to really bring it out. I like your field of view and with more hours you should star to bring out the faint detail in the surrounding halo.

[Dave882]

Thanks Paul- yes I’d love to add to the data with some much narrower-band data or from a darker location. It’s very difficult processing the faint jet cause it’s tempting to just boost saturation etc but then you’re potentially creating detail from the noise. Such a balancing act. Cheers