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(IAAC) Obj: M1-79 (PK93-2.1, png93.3-2.4) - Inst: 20" f/5 dob



Observer: Lew Gramer
Your skills: Intermediate (some years)
Date/time of observation: 14/15 May 1999  06:00 UT
Location of site: Stinson Lake, NH, USA (Lat 43N, Elev 400m)
Site classification: Rural
Sky darkness: 7.0 <Limiting magnitude>
Seeing: variable 3-8 <1-10 Seeing Scale (10 best)>
Moon presence: None - moon not in sky
Instrument: 20" f/5 dob reflector
Magnification: 70x, 120x, 210x, 360x
Filter(s): None, UHC, OIII
Object(s): M1-79 (PK93-2.1, png93.3-2.4)
Object category: Planetary Nebula.
Object class: 4
Constellation: Cyg
Object data: mag 13.2 14.4m*  size 38"x27"
Position: 213700.6+485612
Description:
[This is the first in a long series of observing logs made this May at the
peaceful mountain-meadow observing site near a lake-side cabin that Barrie
Sawyer has chosen to share with fellow members of the North Shore Club...]
--
I spent considerable time tonight searching for this tough object, logged
not too long ago by our own Yann Pothier. It seems relatively easy to find,
lying as it does a mere 1 degree NE of the bright binocular OC M39. However
none of the images or descriptions I had seen prepared me to find what was
a nearly stellar object for me at low power! Careful and repeated sweeping
of the appropriate area turned up nothing at 70x: it was only when I broke
down and star-hopped with the fortuitously faint stars of Chart D-07 in my
Herald-Bobroff "AstroAtlas" at 120x, that I noticed this barely non-stellar
blip amid a subdued sprinkling of mag 10 and 11 stars. Most prominent among
these was a pretty Keystone shape of stars mags 9-10. The target lay at the
center of this Keystone, whose long edges stretch N-S. At lower powers, the
little nebula presented an underwhelming image. However, as seeing briefly
settled and I cranked power to 360x, I could finally unequivocally discern
the elongated nature of this PN. It had a somewhat irregular, "fat peanut"
shape in direct vision, with near perfect N-S orientation. The N "lobe" was
somewhat brighter. Screwing in a UHC and then an OIII had little effect for
me tonight: the OIII did enhance the irregularity of the nebula, but failed
to appreciably increase its 20"x10" size. Reviewing this log later, against
Yann's and Jeff Bondono's descriptions, as well as the DSS image on the Web,
I had to conclude that what I actually observed tonight was the inner core
of this nebula, while these observers (under better conditions) had logged
the outer ring of this very unusually-shaped (proto?)planetary. Perhaps some
Summer night, under cirrus-free conditions, I can log this outer ring also!
--
Object data thanks to dObjects: http://www.eaglequest.com/~bondono/dObjects
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