RCW 58 rarely imaged

[gregbradley]

I imaged this one a few years ago but the seeing wasn't that great.

I was at my dark site on the weekend and its not far from Eta Carina so a good target for the early evening.

Its mostly a Ha object but there is some very very faint O111 as well. I took about 50 minutes and it looks like it would take at least 3 hours to get a decent amount of data. Maybe another time.

I was pleased with the tracking accuracy of the AP1600.

Taken with a CDK17 and a QHY600m photographic camera with 5nm Astrodon filters.

Best viewed as the large size:

https://pbase.com/image/171682364/large regular size.

https://pbase.com/image/171682364/original large view (the best view).

Greg.

[JA]

Wow Greg, Lovely Image :thumbsup:
Looking at it I am really struck with a feeling of the vastness of space.

Best
JA

[multiweb]

Fantastic shot Greg. Beautiful field and details. One for the cool wall. :thumbsup::thumbsup::thumbsup:

[markas]

Splendid image! I wonder what more time will bring? Thanks for showing this rare beast.
Mark

[Bassnut]

Gee Greg, Very good, much detail on the original size. The star colour is nice and guiding looks to be perfect.

[Geoff45]

Nice shot Greg. As you say, more exposure may be good, but you have certainly got some crisp detail there.

[AnakChan]

Great shot Greg. I've not heard of RCW 58 and your pix has definitely piqued my curiosity to research more about this. I can imagine this must be difficult capture and probably only under very dark skies.

[gregbradley]

Thanks JA. Yes it looks very solitary out there by itself in that star field.

Greg.

[gregbradley]

Thanks JA. Its fairly close to Eta Carina surprisingly but nothing else in that field except a lot of stars so it definitely gives the impression of vast space.



Thanks Marc. I got the RGB before the moon came up and the Ha during the moon being up. The 5nm Ha filter is good when the object is not near the moon.



The Ha is quite well exposed its the O111 which is super faint. So it would take probably 2-4 hours of O111 to show much. Its mostly just a ring around it in O111. I did take 40 mins of O111 but I couldn't get it to show through.



Thanks for that. Its a nice long focal length object.300 second exposures on the QHY600m 2x2 retained star colour and I was happy about that as CMOS can lose star colour easily being so sensitive. The guiding numbers at times seemed quite bad and I was surprised initially to see perfect round stars. It must be the PEC curve causing some larger guide errors but keeping it on track. Clear skies, no wind, conditions were ideal.




More exposure on O111 would be the go as there is something there just very very faint. I have 40 minutes and I did manage to see what it was but just couldn't blend it in and show it. Too weak.



No, I think this is a target you could image from home as its a Ha object mainly. The RGB stars would need a decent dark night though.

Greg.

[strongmanmike]

Eeexcellent shot Greg, quite beautiful really :thumbsup: An intriguing object for sure, considered hitting it myself buuuut as you know best plans :rolleyes:

How good are AP1600GTO's..? bloody brilliant, I love mine, no encoders, no PEC, no AO and polar aligned using polar scope :D

Oh....and nice to see something other than my wife's beloved Fighting Dragons :scared: :lol:

Mike

[gregbradley]

Thanks Mike. It was a good night and its nice to having everything playing nicely together. The AP1600 is a wonderful mount.

Greg.

[PKay]

Quite interesting Greg,

but what I found more interesting was looking at all your other work!

Some serious dedication and skill :cool2:

[gregbradley]

Thanks Peter, most kind of you.

Greg.

[Andy01]

Very cool target & well found Greg, :thumbsup:
(Is there an RCW reference atlas some where you can share?)

Thinking about the science behind this. It's my understanding that Wolf-Rayet stars are superheated O3 rich giants, creating nebulas from swirling superheated stellar winds, such as can be found in SH2-308, Thors' Helmet and NGC 2020 in the LMC.

So I'm curious as to why the O3 signal is so weak here.
Maybe that's a question for the Astrophysicists here to answer? :question:

Well done. :)

[gregbradley]

Thanks Andy. No I don't have an RCW catalogue unfortunately.

These Wolf Rayet objects though are quite interesting imaging targets.

Greg.

[JA]

Hi Greg & Andy,

When I first saw Greg's image (:thumbsup:) I had a look for it in Stellarium to see where it lives, and although it didn't have an image of the gas cloud for it, it did recognise RCW 58 and show the central star (V385 Car) and pinpoint the location. I also randomly picked another "RCW something" and it also showed up, so Stellarium includes the RCW star catalog, in a fashion.

BTW the random RCW I checked was RCW 57. It came up as being listed under 3 names/catalogues, namely NGC3576, RCW 57 & Ced 113a, otherwise known as The Statue of Liberty Nebula

Best
JA

[Paul Haese]

Lovely image Greg, very delicate looking processing. Well done.

[gregbradley]

Thanks Paul.

Processing was deliberately minimal.

Greg.

[marc4darkskies]

Yes indeed, a beautiful and well processed image of a very interesting object Greg. I've never actually seen it before. Very nicely done :thumbsup:

[gregbradley]

Thanks Marcus. Its an odd one and not too many examples of it.

Greg.

[Joshua Bunn]

What a cracker image Greg, well done indeed!

[gregbradley]

Thanks very much Josh. You're adapter held the camera very nicely!

Greg.

[Joshua Bunn]

Thanks Greg :)

[Ryderscope]

Good work Greg. The RCW catalogue is a great source of less imaged Ha regions that make for nice targets

[astronobob]

Striking target & intertesting indeed, Greg, Noice image as always also :thumbsup:

[gregbradley]

Thanks for that. Do you have a copy of the RCW catalogue?



Cheers Bob.

Greg.

[Retrograde]

Gorgeous image Greg.
You've picked up some nice structure in this faint object.

[Ryderscope]

Here is a link to a copy of an integrated RCW_GUM_SH catalogue (https://www.dropbox.com/s/06mpilj1793z60j/RCW_GUM_SH_Integrated.xls?dl=0) that I found some time ago. I've saved it to a shared dropbox file. Let me know if you have any issues downloading it.

CS,
Rodney

[gregbradley]

Thanks Pete. I imaged it before at home and the image was a bit soft. This image was taken at my dark site with a much larger scope, the new QHY600m camera which is very sensitive and on top of that it was good seeing.

Sometimes it all comes together and makes up for the much more common times that don't!

Greg.

[gregbradley]

Thanks very much Rodney. I got that. A lot there to explore.

Greg.