Object of the Week January 6th, 2019 - IC2149

IC2149
PK 166+10.1

Planetary Nebula

Auriga

RA 05 56 23.9
DEC 46 06 17

Size: 12”

Mag: 10.6

CS Mag: 11.3


Discovered in 1906 by Williamina Fleming at Harvard College Observatory. As Fleming and her colleagues recorded positions of countless stars on photographic plates, they also searched for new objects as they inspected plates coming from the 8” f/5.5 Bache Refractor. That scope was equipped with an objective prism to help record spectra and Fleming noticed that one star in Auriga had bright spectral lines resembling that of a “gaseous nebula”, a common name back then for what would become known as planetary nebulae. IC2149, as Flemings discovery became to be known, would be just one of forty-three entries Fleming would make into the Index Catalogue.


Easily located a little over a degree N/NW from Beta Aurigae and 40’ from Pi Aurigae, IC2149, will reveal itself in a variety of telescope sizes. In smaller telescopes and/or low power, IC2149 appears as a stellar glow around its 11.3 magnitude central star and can be unimpressive. But with higher power, IC2149 becomes a worthy visit. IC2149 will appear as an elongated glow with a PA of -23° and a bright central star. Many online reports indicate the nebula to have defined edges but after my only observation in 2012, I found just the opposite to be true as I didn’t observe crisp edges. Using Jimi’s 48” on March 25^th, 2012, with a magnification of 488x, my notes read - Nice PN. Oblong Shape, very diffuse edges. Reddish color in the outer shells with a knot on SW side. We used a NPB filter this night with above average seeing and transparency. If you don’t have an NPB filter, an OIII filter is will suffice as a filter is definitely an big help here. I noted reddish hues to the outer fringes of diffuse edges to the nebula, something I haven’t seen mentioned in online observations.


So, before it gets too late in the season, give IC2149 a chance, particularly if you have access to dark skies and larger glass. It’s definitely worthy of a look!


And as always,


“Give it a go and let us know!”






Attachment 3295
Picture credits: Patrick A. Young, Donald W. McCarthy,
Craig Kulesa, Karen A. Knierman, Jacqueline Monkiewicz (Steward Observatory),
Guido Brusa, Douglas Miller, Matthew Kenworthy (Center for Astronomical Adaptive Optics)

Hi ,
Here's my observation from 10/14/2017; planetary nebula in Auriga; magnitude:10.6 ; size:12" ; small but fairly bright; elliptical shape; 11th mag. central star observed; 4.5 Delos eyepiece used at 352x magnification with my 14.5 Starstructure Dob f/4.3 Attachment 3296

Under average seeing and transparency I noted: bright bar around bright CS with two knots at its ends; NE knot brighter and sometimes (not sure) double structure popping in and out of view; SW knot fainter and smaller and a little offset to the N; some structures starting from the SW bar ending - brighter part offset to the NW and a very faint, only suspected structure to the SW; no color detected; both knots do not react on [OIII] filter

sketch: 27", 837x, NELM 6m5+, Seeing III
Attachment 3297

Here are notes through my 18-inch. Only the northeast knot was noticed (this was without prior knowledge).

Easily picked up at 175x as a fuzzy bluish "star, typical of high surface brightness compact planetaries. At 450x, the bright mag 11.6 central star is encased in a high surface brightness, elongated halo, extending ~14"x8" E-W. The following end is a bit tapered and the halo on this side appeared brighter with the impression of a very tiny embedded knot. At 568x a virtually stellar knot was definitely visible just a few arc seconds following the central star within the halo. Images confirm this ionized knot or flier.

Hi,

I think seeing is the key for a successful observation of this small and bright PN.
Here are my notes:

September 29, 2017 3:00 UT, SQMLZ 21.56 S 1.7 "NELM(UMi)6.4/VI4 6.6/VI5, Southern Alps
x125 ES 25/100
Beautiful night, great turbulence target the quasi zenith very good observing conditions. At this power PN is reduced to a very small and elongated fuzzy patch, very blue, with obvious CS *, more blue
x890 Nagler 3.5mm without filter
The shape and boundaries of the NP are accurate. CS * is obvious, nearby stars are small but well regarded. Cloudiness perpendicular to the main axis is difficult, but recognized after viewing the image of the HST. Midrib on Part E was noted without knowing; it is perceived fine. The bluish color is pronounced C130 / S40 or 50; CS * is 70 or S60!

Attachment 3298

I have observed that PN in 2009 and 2011, and it is interesting to compare these findings with that tonight. The three were performed with the same instrument, the same eye, Nagler and Ethos, in the same site for the past two and almost as good site (High Provence) first. The only difference, but significant, is that turbulence was average for the first two and very good for the last.

Attachment 3299

Detailed reports at: http://www.deepsky-drawings.com/ic-2149-3/dsdlang/fr

Clear skies
Bertrand
http://www.deepsky-drawings.com

I have an observation of IC 2149 from 2014:

"A small but fairly bright PN in Auriga that has an oblong shape that pops out with averted vision. The seeing is much too soft to see any detail, but 2149 is at least easy to find. 253x and 408x, 21.23 SQM."

Attachment 3300 Attachment 3301

According to my notes the very next night had wonderfully steady seeing, but unfortunately I didn't go back for another look.