Sharpless 2-112 and other Summer Stunners
From: Bill Ferris (billferris_at_aol.comic)
Date: 06/18/04
- Next message: Al: "Re: Kerry on Bush Space Plan: At least he's in favor of Saving Hubble!"
- Previous message: CHASLX200: "Re: Semi-Apo"
- Messages sorted by: [ date ] [ thread ]
Date: 18 Jun 2004 00:46:08 GMT
Two nights ago on a whim, I decided to take advantage of northern Arizona's
seasonal run of photometric nights and catch some photons with my 10-inch
Newtonian. Going through some old observing lists, I found several that had
been printed off Jim Shields' excellent "Adventures in Deep Space"
(http://www.angelfire.com/id/jsredshift/index.html ) website. I grabbed the
"Seasonal Favorites"
(http://www.angelfire.com/id/jsredshift/favorites.html ), loaded my gear in the
Rodeo and hit the road for Anderson Mesa.
Three of the four objects I observed were firsts for me. All were interesting
and challenging in their own right.
Sharpless 2-112: http://members.aol.com/billferris/sh2112.html
What a gorgeous bit of nebulosity! Sharpless 2-112 is an emission nebula tucked
away in northern Cygnus. Deneb lies just 1.3 degrees to the east-southeast. My
sketch (see above link) presents an 82X view in my 10-inch Starfinder
Newtonian. An OIII filter was used to enhance contrast. 9.2 magnitude SAO 49801
is at the center of the field. Sh 2-112 ranges broadly toward the east over a
10'x12' area. The nebula shyly displays delicate filamentary structure to the
eye. It's almost boxy in shape with brighter west and north sides. There's just
a hint of nebulosity detatched west of Sh 2-112. I would love to
observe this through a 15-inch or larger instrument. Twenty-three stars frame
this portrait.
IC 4593: http://members.aol.com/billferris/ic4593.html
Planetary nebulae offer some of the most interesting observing targets in the
night sky. They can appear linear, square, circular or any of several different
shapes. This guy, IC 4593, resides in southern Hercules along the border with
Serpens. My drawing (see link) captures the nebula's appearance in the 10-inch
Starfinder at 247X, a magnification achieved by pairing a Meade 13.8-mm SWA
eyepiece with TeleVue's 3X Barlow. IC 4593 is tiny, just 30" in diameter, and
has a bright 11.2 magnitude central star. The central star burns through the
surrounding nebulosity intermittently as I flit between direct and averted
vision. A 9.4 magnitude star blazes 5' to the northwest and just inside the
field boundary. Another four stars complete the view.
NGC 6765: http://members.aol.com/billferris/n6765.html
I came upon this odd little treat in southern Lyra. NGC 6765 is a planetary
nebula with a photographic magnitude of 13.1 and an odd elongated form. It was
a challenge to find with the 10-inch. And once located, this little guy would
not easily give up his secrets. My sketch (see link) presents a 129X view in
the Starfinder, both with
and without the OIII filter. A twelfth magnitude GSC star lies at the very
center of the rendering. Just 2' to the northeast is where NGC 6765 is seen.
The planetary was first detected as a tiny round dot just slightly brighter
than the surrounding sky. Switching between filtered and unfiltered views
reveals more nebulosity to the
southwest. Overall, NGC 6765 covers a 45"x10" area. The 16th magnitude central
star was, of course, not seen. Another 33 stars frame the view.
Regards,
Bill Ferris
"Cosmic Voyage: The Online Resource for Amateur Astronomers"
URL: http://www.cosmic-voyage.net
=============
Email: Remove "ic" from .comic above to respond
- Next message: Al: "Re: Kerry on Bush Space Plan: At least he's in favor of Saving Hubble!"
- Previous message: CHASLX200: "Re: Semi-Apo"
- Messages sorted by: [ date ] [ thread ]
Relevant Pages
|
