Formal Wear for Planetary Nebulae

Bow Tie Planetary in Northern Cepheus
  
  In the northern reaches of the constellation Cepheus one can find a planetary
nebula designated NGC 40 or Caldwell 2. This planetary has a bright easily seen
11.5 magnitude central star. The star is extremely hot and was formerly a
Wolf-Rayet star that is currently progressing to the white dwarf stage of stellar
evolution. The portion of the nebular shell I could see was round in appearance
and looked to be about 25” of arc in diameter. The shell glows at 11.7 magnitude
and is best seen by averted vision when not using a nebula filter. With a narrow
band light pollution filter, the nebular shell looked brighter and 30% larger. I
found the unfiltered view more pleasing to the eye and sketched the view without a
filter. Photographs of this object show it to have a pair of bright margin ring
arcs in the east-west direction. These arcs and the central star give the nebula a
bow tie like appearance. I was not able to see bright ring arcs under my observing
conditions with a  10” telescope. The shell spans a bit more than one light year across and lies 3500 light years away. Cepheus is in a favorable viewing location this time of year for northern latitudes.
  
  
  Sketching:
  
  Date and Time: 9-15-2007, 2:30-2:55 UT
  Scope: 10” f /5.7 Dobsonian. 21mm and 12mm eyepieces 70x and 121x
  8”x 12” white sketching paper, B, 2B graphite pencils, scanned and inverted, star
  magnitude adjustments using Paint
  Averted vision was a very useful aid in drawing the extent of this planetary nebula.
  Seeing: Pickering 7/10
  Transparency: above average 4/5
  Nelm: 4.7
  
  Frank McCabe