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(meteorobs) Comet info & atlases...
Jonathan -
You wrote:
>I have found another comet suspect, at ~ magnitude 9. I used a 6" Newt., and
the coordinates were about 4 hours, 16 minutes, and a declination of +53.
Figured I might comet, I mean comment, on this one ;) You had posted another
suspect object earlier, which you subsequently determined was an NGC. I didn't
comment on it then as your area, plus/minus 20 degrees I think you said, was
<far> too large a margin of error for any of us to be able to easily help you!
(And don't forget too, that this is a <meteor> list... not everyone on this list
is necessarily as interested in comets!)
I think several things might help you out:
1. What star atlas are you using?? The better your star atlas, the more
'suspect' objects you can eliminate. Some star atlases go to much fainter
magnitudes than others. Consulting my Sky & Tel and catalogues here, they list
faintest magnitudes as follows:
6.5 - Tirion's Bright Star Atlas 2000.0
6.5 - Norton's 2000.0
8.0 - Tirion's Sky Atlas 2000.0
9.0 - AAVSO Atlas
9.5 - Uranometria 2000.0
11.0 - Millennium Star Atlas
With a 6 inch Newtonian, you should have at least something like the Tirion's
Sky Atlas 2000.0, with its mag 8.0. I wouldn't recommend the AAVSO atlas to
you as it was intended for other uses. Uranometria, although more expensive, is
very good. It's the one I use on my lap all the time with my scope, when I'm
star-hopping to faint galaxies and other objects. (My scope is a 4.7 inch, but
easily comparable to yours aperature-wise as I have no central obstruction.)
With an atlas properly matched to your scope size - and hence the star fields
you see in your scope - you can figure out what most objects are.
2. Check to see what comets are out there, that are visible in amateur scopes.
Might I recommend Don Machholz's web page:
http://members.aol.com/cometcom/index.html
It gives positions for comets that amateurs can see.
In summary, make sure you have a decent atlas for your scope - to check out what
<isn't> a comet, and stay tuned to Machholz's 'Comet Comments' on his web page -
to check out what <is> a comet.
And then, if you've plotted your suspect object fairly well on your atlas, and
if your suspect object isn't listed <anywhere>, let us know and we'll see if we
can help you out!
- Cathy
Comet fan in the Great White North....