View Full Version here: : He2-111, a surprising planetary nebula
13-06-2012, 01:09 PM
Dear all, I propose this time a picture of a field around Alpha Centauri that will be a surprise for many of you. In fact the fascinating object at the right of Alpha Centauri is a very little imaged planetary nebula, Hen 2-111, that is usually known to be a bright peanut shaped PN with a size of only 29 x 15 arcseconds. However, its most visually striking aspect is a faint giant ionized halo that spans 10 x 5 arcminutes! This extreme structure was discovered by B. Louise Webster in 1978 in deep photographic plates taken with the (at the time) Anglo-Australian Observatory. At an estimated distance of 7800 light years, the entire nebula spans approximately 23 light years! The halo is actually a rare bipolar outflow and the other notable planetary nebula known to exhibit this unique feature is the northern hemisphere nebula KjPn 8 in Cassiopeia.
The link (recommended the original resolution “O”):
Henize 2-111 (http://www.glitteringlights.com/Images/deepsky/13667287_7Mtr58#!i=1881101068&k=CRSRnSZ&lb=1&s=X3)
This feature is so little known that in fact I was not able to find any other image in the net revealing the halo apart few B&W images on professional literature. If you are aware of other deep images it would be interesting to compare the view.
To the right of Hen 2-111 is the attractive pairing of the open clusters NGC 5617 and Pismis 19. NGC 5617 is the larger and younger of the two and despite its apparent youthful appearance, it is actually an intermediate age cluster with an estimated age of 80 million years. Contrastingly, the smaller rich condensed cluster Pismis 19 appears much older than NGC 5617 and indeed its golden ancient light betrays its great age of 800 million years! It is at a similar distance to Hen 2-111 of about 7800 light years whereas NGC 5617 is much nearer at 5000 light years. However, it is subject to severe reddening due to interstellar dust between us and the cluster and would shine more brightly if this dust was less prevalent. Also barely visible in the glare of Alpha Centauri is a round broken roughly circular shell, which can be seen to the north of the halfway point between Alpha Centauri and Hen 2-111. This is the supernova remnant G315.4-0.3, which was discovered in a radio continuum survey by Anne Green in 1974 and identified as a supernova remnant in 1975. However, its extremely dim optical shell was discovered recently in 2011 in a search for new supernova remnants in SuperCOSMOS Ha Survey (SHS) images by Milorad Stupar and Quentin Parker.
I hope you will enjoy the view ;)
13-06-2012, 01:24 PM
Love the little known gems you keep coming up with.
13-06-2012, 02:01 PM
Sensational image Marco congratulations. This object is listed in the revised Hartungs as object 646. I have viewed this years ago using a 37cm and O111 filter. There are notes that there is some positional co-incidence with a "new star" recorded by Chinese observers in AD185. Though another nearby object RCW86 is the likely Supernova remnant for this event.
Some interesting sites below.
13-06-2012, 02:59 PM
Well that's a unique view Marco, fascinating and nicely processed especially considering the 4th brightest star in the sky is in the field :eyepop:, who would have thought? :thumbsup:
13-06-2012, 03:12 PM
Outstandingly interesting and a well processed image
13-06-2012, 03:31 PM
Here you go Marco. I was using Alpha Cent to focus and test tracking and had this image. It is a 960s single exposure without any correction in NII 3nm. The Bright star is Alpha Cent. 4MB
I wondered about the faint what looks like a SN remnant to the right of the image and thought I must explore this further. There is some faint signal in NII of your object.
13-06-2012, 04:47 PM
Wonderful image Marco.
Super professional processing and of course such a unique object.
13-06-2012, 05:14 PM
Amazing image of something completely new to me!
13-06-2012, 05:40 PM
Good catch Marco!
13-06-2012, 05:42 PM
Marco ... this is an amazing result.
Perfect processing for me ... and interesting objects on.
All the best,
13-06-2012, 07:23 PM
Great stuff! I learned something new today - thanks Marco.
13-06-2012, 07:43 PM
Yep, nice one Marco.
13-06-2012, 07:47 PM
There are several obscure PN catalogues so great to see a new PN shown here.
13-06-2012, 08:08 PM
Wow, that's an amazing image and some very interesting info. The processing is superb as always, it must be a challenge to get such an image with Alpha Centauri in the field!
Great choice of target and well done, thanks for sharing this.
13-06-2012, 09:42 PM
What an incredible field! Marco you're a legend. Amazing and hard to find stuff like this just blows me away.
Thanks so much for posting.
13-06-2012, 10:07 PM
A fine image indeed Marco and new!
14-06-2012, 09:42 AM
Very interesting capture and new, as Martin has said. Well done! :thumbsup:
14-06-2012, 04:08 PM
First of all I want to heartly thanks all of you for the appreciation and let me clarify that the merits of having found out this hidden gem are of Sakib Rasool, in this case I am only the humble labourer that managed to collect the light ;)
Thanks for the very interesting note Peter, I was not aware of this further details :thumbsup:
thanks Bert, you collected a lot of light considering the short exposure, my compliments!
Thanks Rolf. Managing the light of ACent was the most difficult part since I had nasty reflections everywhere in Ha. To fix it I had to take several group of images keeping the star outside with different offset to null the reflections without loosing the light from the nebulosity :screwy:
Again, thanks for the appreciations!
14-06-2012, 06:23 PM
Very challenging shot and text book processing again. Superb field. :thumbsup:
15-06-2012, 06:55 AM
Beautiful image Marco. Mikes right -who'd have thought to image here?
15-06-2012, 08:26 AM
Lovely work Marco. The PN and as Bert pointed out what looks like a SN remnant really stand out despite the glare of Alpha centauri. Processing is very smooth and I had no idea that these objects were in such close proximity to this often viewed star.
15-06-2012, 08:48 AM
Wow, Marco. I love planetary nebula and their unique characteristics. Thanks for the view. All the best.
15-06-2012, 09:43 AM
Thanks Marco. I found I had two 960s exposures so I corrected them for darks and flats and squeezed out what I could for you.
The main reason I invested in my new system was to image very dim stuff in a moderately wide field. The Astrodon 50mm square 3nm filters are not cheap but their performance is superb. From my mildly light polluted site it was the only way to go.
This image shows just how much NII is out there and I have barely begun to look.
16-06-2012, 02:30 PM
Fantastic work. I will have to have a go at that myself. A most inspiring image and the follow up ones by Bert also amazing, uncovering the majesty of the deep southern skies, some of which has only recently been discovered.
16-06-2012, 09:46 PM
Well done Marco! That is a wonderful image. It is amazing what is around this star which I see so often :thumbsup:
18-06-2012, 06:49 PM
Thanks Scott, definitely the southern skies are full of quite unknown gems, I am enjoying a lot going to "discover" them as well :)
Great Bert, with your system speed and field of view I hope you are going now for a deep narrowband composition of the area!
Thanks Paul for the appreciation
That's the beauty of our hobbie, there are so many things out there that ones never end to get surprised :)
19-06-2012, 08:37 AM
A great capture Marco.
29-06-2012, 12:27 PM
Hey, I saw this (http://apod.nasa.gov/apod/ap120628.html) on some obscure backwater NASA site today :confuse3:..thought it might get missed :shrug:
29-06-2012, 01:33 PM
Yeah me too, congrats.
29-06-2012, 08:42 PM
Beautiful - congrats on the well-deserved APOD!
30-06-2012, 09:40 AM
Congrats on the APOD Marco!
30-06-2012, 12:57 PM
Congrats on a well deserved APOD Marco. I somehow missed this one but what a striking image it is! I love it! :thumbsup: Most people avoid such bright stars but in this composition it's beautiful!
30-06-2012, 01:44 PM
Thanks Mike, Paul, Dave, Greg and Marcus for the congratulations :thanx:!
vBulletin® v3.8.7, Copyright ©2000-2013, vBulletin Solutions, Inc.