View Single Post
  #2  
Old 30-12-2010, 10:42 AM
ngcles's Avatar
ngcles
The Observologist

ngcles is offline
 
Join Date: Dec 2006
Location: Billimari, NSW Central West
Posts: 1,581
Hi James & All,

Thanks very much for posting your observations James -- much enjoyed.

A UHC filter shouldn't be of assistance with the nebulosity surrounding the Pleiades. It is a reflection nebula and has the same basic colour as the stars themselves. It has no emission component because the stars in the cluster don't put out enough high-energy U.V light to ionise Hydrogen (You need O3 to O9 stars to do that sort of thing). A UHC filter blocks starlight and in doing so blocks reflection nebulosity. Go without filter !

You mention the cluster next to M35 -- I think this is a typo as it is NGC 2158. A distant (but quite large) open cluster that is somewhat reddened compared to M35. Believed to be a G.C up until about the 1970s when someone did a C-M diagram that showed it's decidedly "open" character.

M46 and its embedded planetary (NGC 2438) are excellent. The planetary would be an excellent target by itself.

"Zorro ..." yes, very apt moniker. I won't be able to get the theme music for Zorro out of my head now for the rest of the day!

Hoping for continued clear skies. I'm aiming to get out to my "nearly dark" site tonight.


Best,

Les D
Reply With Quote