PN Halos

[Jens Bohle]

Hi everyone,


this is my first post here at deepskyforum and probably the first post from germany I want to start with an appeal to the advanced observers.

In a few weeks we start our annual deep sky meeting here in Germany (we call it “Deep-Sky-Treffen, DST and it starts back in 1999). I want to give there a lecture regarding PN Halos.

Beside my own observations I want to show other observations. So I will be very pleased if some of the guys here could send me some observing reports of these outer PN structures. Well known examples are the Halos of M 57 and M 27. But these are not the only Halos for visual observers. For example there is well detectable glow around the “Blue Snowball” or the well known “Cat´s Eye” with it´s bright condensation IC 4677.

The structures around the “Ghost of Jupiter” NGC 3242 are Halo-Structures and maybe a target for tough guys with large Telescopes under true dark skies.

So please, if you have any observations regarding these “outer structures” please send me a note.

Best regards from Germany, Jens Bohle

[Jimi Lowrey]

Welcome to DSF Jens,

In My 48" reflector the halo of the Blue Snowball is very large and extended. with a DGM NPB filter it really lights up the outer shell and is easily see with direct vision.

One of if not my favorites is NGC 2371 the Bi polar parts of it remind me of the Mickey mouse club hat. I remember Steve Gottlieb was take with this PN the fist time he got to see it in the 48 I hope he will jump in and share his notes on this object.
ngc 2371.jpg
Click to Enlarge

[Steve Gottlieb]

Here are my notes on NGC 2371/72 from last April with Jimi's scope. As we moved fairly quickly from object to object, this is really the obvious structure that was visible with a first look and likely additional details would have been noted with more attention.

I was stunned by the view of this bipolar nebula as there was so much intricate detail it had little resemblance to the previous views with my 17.5" and 18" scopes. The most prominent feature was two, irregularly round, very bright nodules on the SW and NE side of the boxy, elongated central region. Each nodule was distinctive and varied in surface brightness and shape with the SW lobe brighter. Filamentary streamers or a "hairy tail" extended from the NE node towards the NW and similar wisps extended mainly SE from the SW node, creating a sense of rotation around the fairly bright central star. The interior and sides were filled with much fainter nebulosity. A very faint filament connected the main lobes on the NW edge. Detached from the main 1' structure were two amazing outer wings, symmetrically hanging 1' NW and 1' SE from the central star. These wings or "polar caps" were easily visible without a filter at 488x and both extended ~40"x10" in a SW-NE orientation, increasing the total diameter of the planetary to 2'. A mag 13.5 star lies 1.5' NW and a mag 16 star is 50" NE of center.

[Steve Gottlieb]

As far as the outer halo in NGC 3242 ("Ghost of Jupiter"), here are my notes again in Jimi's 48" --

48" (4/1/11): remarkable view at 488x with a high contrast, high surface brightness double ring structure and an outer third shell. The small inner lens has an electric turqoise color and is elongated 3:2 NW-SE, ~25"x15". At the SE end of the major axis of the inner ring is a well-defined, bright knot. The irregular inner ring is also brighter and thicker along the NW end, though not as bright or sharply defined as the SE knot. The dim central portion is punctuated by the bright central star. The outer ring is rounder and extends ~45"x35" NW-SE, with the limb unevenly lit. The greenish color is not as intense in the outer ring. Between the two main rings the nebulosity has a pinkish hue. The main structure was surrounded by a low surface brightness outer halo, at least 1.5' diameter, which significantly increased the total size!

[Marko]

Since one of my favorite objects, Ngc2371/2 was mentioned I'll share my observation with 18" dob which was from 3000 feet place called Willow Springs where I was above the fog and it was magical in a way. Magical from the fog but also from finally seeing the two wings.

Here is my observation:

NGC 2371 Gem Plan 07 25 34.8 +29 29 22 13.0p 55.0" NPB filter Two closely spaced lobs < 1/20 fov [.9'] size aligned at 45dPA with each other. The leading lobe to the SW is brighter and even stellar in appearance with high concentration. A slight gap between them with the best gap detection to the NW. Trailing lobe is dimmer and hints at possible stellar center. 1/3 of the way from bright core to a very faint star 1/8FOV WNW I can detect a faint glow of the leading 'wing'. This with averted only but is very clearly present. Currently 21.6 on the SQM in that area of the sky. The trailing lobe is on the opposite side of the main objects and is the dimmer of the two wings and available averted over 50% of the time for seconds at a time. In moments of good seeing both wings and the dual planetary can be seen. The wings are at about 120dPA. H1 12/12/10 00:35 WSprbobA 278 7mmNag 18SmF3.7PC


My best Ghost of Jupiter view was through a 33 inch Dob also at Willow Springs but at 2000 feet (no fog of course). This was a real treat.

NGC 3242 Hya PN 10 24 48.0 -18 38 00 8.6 40"X35" GhostOfJupiter: 1' dia 1.2EL 30dPA Amazing view. GreenishBlue. Distinct central star visible. Distinct bright and distinct definition donut even density ring slightly elongated. Then more dark gap then a much fainter but broader, less defined ring outside that. Finally a very faint glow fading gradually off outside 2nd donut.2 H1 DM SAL S57 RA C59 03/27/09 23:35 WSprDSR 165 27mm? 33DobZillaF5 21.60

[Jens Bohle]

Thanks a lot for your replies!

As for NGC 3242: has anyone observed the outer halo of Jupters ghost? This faint structures are visible on the POSS-blue prints ~8,5' sw as a part of the giant Halo around the "small" mainbody of the nebula.