The Burning Blue Dragon in Cepheus - Supernova remnant CTA 1 with NGC 40

[gorann]

CTA 1 is a rarely imaged supernova remnant (aka SNR G119.5+10.2) in Cepheus, consisting of a 1.5 degree filamentary shell, so quite large.  However, it is extremely faint and my first attempt to image it a year ago during a moonlit night using NBZ dual-band filter was not very successful., although the result was interesting enough to merit a second attempt when the moon was gone. The second attempt on the 27th Dec 2021 was more promising but then I could only use the subs from one of the RASAs in my double rig, since the stars were poor due to tilt in the other. However, now when I have StarXTerminator in my toolbox I could use all the 124 subs and get much deeper.

And out came this blue dragon! (at least that is what it looks like to me😁)

The bright red/yellow object near the center is NGC 40, a small planetary nebula. However, they are not interacting but only happen to be on the same line of sight. The distance to CTA 1 is estimated about 4600 lightyears and its age is about 10’000 years. NGC 40 is about 3500 light years away from us and 4,500 years old.
CTA 1 occur in the first list of radio sources published by the CalTech Observatory in 1960, hence the annotation CTA.

So, dual RASA8 rig with ASI2600MC and IDAS NBZ dual-band filter (Ha+Oiii). 124 x 5 min, so 10+ hours. Processed in PI and PS using StarXT and NoiseXT.

EDIT: I added a second version where I used a curve in PS to lift the red signal for more Ha to come through - it made me rename it: The Burning Blue Dragon (but who am I to name nebulae🥴).

 

Cheers, Göran

 

Edited December 12, 2022 by gorann

[Adreneline]

Very nice Göran. Love the colours and depth you've managed to achieve - very sympathetic processing. Adrian

[gorann]

11 minutes ago, Adreneline said:

Very nice Göran. Love the colours and depth you've managed to achieve - very sympathetic processing. Adrian

Thanks a lot Adrian!

I just added a second version with more Ha signal.

[symmetal]

Great image Göran. The 'dragon's eye' star is very conveniently placed. Planetary NGC40 also looks pretty insignificant in comparison. 🙂

Alan

[gorann]

10 minutes ago, symmetal said:

Great image Göran. The 'dragon's eye' star is very conveniently placed. Planetary NGC40 also looks pretty insignificant in comparison. 🙂

Alan

Thanks Alan, and yes I agree - well placed eye!

[tomato]

Very impressive, I’m only viewing them on my phone but they look stunning. 
 

Did you do anything with the star shapes or did you just minimise the stars when you put them back in?

[gorann]

Thanks a lot Steve! I used the stars from the "good" RASA8. And when adding them in PS using a curve to suppress them small imperfections become smaller. Like anything caught with a RASA, it is not full proof for pixel peeping, but good enough I think.

[jjosefsen]

Woah! Really beautiful Goran, brilliant and never seen it before. Impressive! 

 

 

 

 

 

 

 

 

[gorann]

46 minutes ago, jjosefsen said:

Woah! Really beautiful Goran, brilliant and never seen it before. Impressive!

Thanks a lot! Yes, very few images of this faint object and I have not seen any showing the fainter dust around.

 

 

Edited December 11, 2022 by gorann

[AstroGS]

Very nice - well done! Just added this one in my list of must-do targets.

I will give a try with the RedCat51 + 2600MC + Antlia Gold Filter to see what i can get. Probably 10+ hours will definitely be needed.

[gorann]

1 minute ago, George Sinanis said:

Very nice - well done! Just added this one in my list of must-do targets.

I will give a try with the RedCat51 + 2600MC + Antlia Gold Filter to see what i can get. Probably 10+ hours will definitely be needed.

Thanks a lot George!

It is faint so you need a dark site (I am at Bortle 2-3) and a lot of integration time, so the best of luck and build up your stamina!

[AstroGS]

3 minutes ago, gorann said:

Thanks a lot George!

It is faint so you need a dark site (I am at Bortle 2-3) and a lot of integration time, so the best of luck and build up your stamina!

I am at a bortle 5-6 so, probably 15+ hours then. But, love the challenge of the "Blue Dragon" (you had the honours to name it).

Thanks for sharing the coordinates as well. 🙂

[gorann]

15 minutes ago, George Sinanis said:

I am at a bortle 5-6 so, probably 15+ hours then. But, love the challenge of the "Blue Dragon" (you had the honours to name it).

Thanks for sharing the coordinates as well. 🙂

You should have no problem fitting into your FOV.

RA center: 00h10m26s.80

DEC center: +72°55′43″.2

[michael.h.f.wilkinson]

Amazing stuff!

[gorann]

30 minutes ago, michael.h.f.wilkinson said:

Amazing stuff!

Thanks Michael, much appreciated!

[carastro]

Lovely image Gorann.  Oh to have your dark skies.

Carole 

[Lee_P]

Another cracking image!

[gorann]

11 minutes ago, carastro said:

Lovely image Gorann.  Oh to have your dark skies.

Carole 

 

3 minutes ago, Lee_P said:

Another cracking image!

Thanks a lot Carole and Lee, much appreciated. Yes, I love my dark sky, when the weather allows me to see it.....

[old_eyes]

What a fabulous object Gorann. A touch of a Klingon Warbird perhaps? I am really tempted to have a go with this using our mono reduced FSQ 106 in Spain. A slower rig but a mono sensor.

Edited December 12, 2022 by old_eyes

[gorann]

5 hours ago, old_eyes said:

What a fabulous object Gorann. A touch of a Klingon Warbird perhaps? I am really tempted to have a go with this using our mono reduced FSQ 106 in Spain. A slower rig but a mono sensor.

Thanks, and you should go for it, it is an overlooked but remarkable object!

[Stuf1978]

I've never seen this one before, absolutely stunning. Great work as always

[old_eyes]

Göran - just a quick processing question.

Which channels from RGB did you use as O3? I know a lot of people throw away the B and only use the G for O3, remapping that to get the colour they want. Interested in whether you had 3 out of 4 pixels in the Bayer matrix for O3 or only 2. As you had to boost the Ha to get the effect you liked, I wondered how much O3 you started with.

[old_eyes]

Göran,

Do you happen to know your camera angle? I couldn't platesolve your final processed image. It would help me check framing, although I think I am OK no matter what the orientation, but good to check. 

Thanks

 

[gorann]

1 hour ago, Stuf1978 said:

I've never seen this one before, absolutely stunning. Great work as always

Thanks a lot! Yes, it is almost never imaged, probably because it is very faint and few knows about it.

[gorann]

2 hours ago, old_eyes said:

Göran - just a quick processing question.

Which channels from RGB did you use as O3? I know a lot of people throw away the B and only use the G for O3, remapping that to get the colour they want. Interested in whether you had 3 out of 4 pixels in the Bayer matrix for O3 or only 2. As you had to boost the Ha to get the effect you liked, I wondered how much O3 you started with.

The data I get with my OSC through the NBZ filter I process more or less as any RGB colour image so I do not separate the channels. When I boosted the Ha in the final version I just lifted the mid part of the curve for the red channel in PS. So, I have not thrown away any green or blue data🙂

Edited December 13, 2022 by gorann