[Chaos-l] Limiting Mag at various sites

[Stewart-Taylor, Jon]

Hi all. Ms. Sayle asked:

>limiting magnitude for any of the following places on a good night:
>  - downtown Chapel Hill? 

It's normally in the low 2s.  If desired, we could make determining the
LM part of the activities for the night, using the "count-the-stars"
method: "Count from here, LM=___.  Now count from home, LM=___.  See
what light pollution does?" kind of thing.  Orion should be visible.  If
Orion is out of reach, we could try a different constellation, but
almost everybody can _find_ Orion.

>  - The "darker" parts of Chapel Hill, but still within city limits?

In my front yard (intersection of Honeysuckle and Booker Creek) it's
usually around 3.8, but on Really Good Nights it can reach 4.1.

>  - Ebenezer Church Recreation Area at Jordan Lake?

Most of the Jordon Lake sites are usually about 5.0, though the light
domes affect that in some directions.

>  - The CHAOS dark site? 

The last time i counted there (about a year ago) it was about 6.1, much
brighter than i expected given how bright things are through 'scopes
there.

>If you're bringing a telescope to this event, what might you be 
>planning to look at?  

Funny you should ask!  I built a page on the web site specifically for
this kind of question: http://rtpnet.org/chaos/whatDidISee.html

For the sundial in mid April, probable deep-sky targets would be M41 (if
accessible), Tau Cma (ditto), M36/37/38 (ditto), Mizar/Alcor (Zeta Uma),
M35, Beehive (M44) in a finder or small scope, Cor Caroli (Alfa CVn),
and of course Saturn.

Hope that helps.

J.
-- 
Jon Stewart-Taylor: joncst at earthlink.net; 919-967-2912	
Chapel Hill Astronomy: http://rtpnet.org/chaos/	
Light pollution information: http://www.ncdarksky.org/