Re: ATM crab nebula

["Bill Prewitt" <bprewitt@neo.rr.com>]

The Crab is one of those things you can detect with a ten, but it isn't a
"Wow" object visually at less than about twice that diameter.
Low surface brightness objects call for big glass or else a CCD.

For ATM planning purposes, the number (N) of "Wow" objects for a given inch
aperture (D) is :
N < 0.15 * D squared

           Bill Prewitt

Webpage of Telescope Making and Caving
(My hobbies keep me in the dark)
www.astrocaver.com


> What should I expect to see with a 10" F7 on a fairly good night?
> Specifically, what should the crab nebula look like?  All I saw was a
'faint
> fuzzy'.  This is okay if I shouldn't expect to see more.
>