(IAAC) Obj: Abell 3 - Inst: 18" f/4.5 Dob

**anonymous@sedna.atmob.org**

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Observation Poster: John Tatarchuk <tatarjj@auburn.edu>

Observer: John Tatarchuk
Your skills: Advanced (many years)
Date/time of observation: 12/16/06
Location of site: 10 miles west of Fort Davis, TX (Lat , Elev 6000')
Site classification: Rural
Sky darkness: 10 <1-10 Scale (10 best)>
Seeing: 5 <10-1 Seeing Scale (1 best)>
Moon presence: None - moon not in sky
Instrument: 18" f/4.5 Dob
Magnification: 110X, 230X, 290X
Filter(s): OIII
Object(s): Abell 3
Category: Planetary nebula.
Class: 
Constellation: Cassiopeia
Data: mag 18.2p  size 60"
Position: RA 2h:12.1m  DEC +64:09'
Description:
This is another of the hardest Abells. Its dimensions are given as 60”x60” and
magnitude 18.2p. However, it was no match for dark Texas mountain skies. After
matching the Aladin Previewer chart to the Cassiopeia star field, I was able
to pick up a very, very faint disk using 110X magnification and OIII
filtration. The disk appeared to be situated just W of a close pair of
magnitude 13 stars. The stars provided some interference, but increasing
magnification to 230X and 290X in an attempt to minimize this interference
decreased the visibility of the nebula. I was unable to hold the disk in
adverted vision, but it was able to be dependably reacquired. Nebula was best
visible at 110X.
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