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(IAAC) Obj: NGC 2022 - Inst: 17.5" f/4.5 dob



Observer: Lew Gramer
Your skills: Intermediate (some years)
Date/time of observation: 9/10 Feb 1999  05:00 UT
Location of site: MIT Haystack Obs., Westford, MA, USA (Lat 43N, Elev 30m)
Site classification: Exurban
Sky darkness: 6.6 <Limiting magnitude>
Seeing: 4 <1-10 Seeing Scale (10 best)>
Moon presence: None - moon not in sky
Instrument: 17.5" f/4.5 dob reflector
Magnification: 57x, 225x
Filter(s): None, UHC
Object(s): NGC 2022
Object category: Planetary Nebula.
Object class: 4+2
Constellation: Ori
Object data: mag 12.4 15.20m*  size 28"x27"
Position: 054206.18+090510.3
Description:
Next up on our tour of duty with the 17.5" Club scope tonight, we went off
searching for the unexpected Orion planetary NGC 2022. We star-hopped from
the lovely star triangle (lambda Ori) at the head of Orion, down along the
E "collar bone" of the Hunter. After first encountering emission/reflection
nebula Cederblad 59 accidentally (see previous log this night), we managed
to sweep back to a pair of mag 8 stars, which point conveniently SE to the
planetary. With low power n2022 was distinguishable from surrounding stars,
but hardly striking. No color or detail could be seen. But at higher power
with the UHC filter, the annular nature of 2022 became immediately apparent.
In addition, a definite brightening could be observed near the middle using
averted vision. At the time, after first deciding it was the mag 15 central
star, I noted it on more careful observation to be clearly non-stellar, and
in any case too bright to be the star. I guessed it to be either nebulosity
surrounding the central star, or maybe an incipient inner ring. Now though,
after viewing some of the available data and images, I have to conclude that
this central brightening was in fact either that central star bloated by poor
seeing, or else some bright knot of NGC2022's internal filamentary structure,
which confuses the eye at this power. Other features were also logged at the
time around the bright ring of nebulosity: the most striking was a seemingly
irregular brightening or knot SSW of the center of the object. Another such
knot, slightly less distinct, was noted an equal distance to the N. Between
these two brightenings, I almost got the impression that I was seeing bipolar
lobes, although their shapes and spacing were definitely more irregular than
the symmetry one expects in true bipolarity. Finally a mere suggestion of an
outer halo was noted to increase the overall diameter of the object by maybe
10", with what occasionally seemed to be an irregular longer lobe on the NW.
--
Object data thanks to dObjects: http://www.eaglequest.com/~bondono/dObjects


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