Re: AAS002511 Run

From: Joe Patterson <*jop_at_astro.columbia.edu*> Date: Sat, 25 Sep 2004 22:05:46 -0400 (EDT) · jop_at_astro.columbia.edu

> Cedar Drive Observatory just started a run on ASAS002511 with the 12".  The
> sky is clear, the star just cleared the obs wall, the moon is just far
> enough off axis that the dew shield is keeping the light from falling
> directly on the corrector plate, and the wind tapered off to nothing over
> the last couple hours, so I said 'what the heck'.  Should be clear all
> night...
>
> What sort of issues should I be aware of doing photometry with the moon this
> bright?

I'm pretty sure you'll be fine all night at that brightness. Especially if
you see that the dew shield is baffling well.  Monday night, now that's
likely to be dicey.  If you have a provision for filters, you can try R or
I filters, which will greatly reduce scattered light compared to a
wide-open bandpass.  (The modulations we study are broad-band, so that
doesn't confuse the analysis.)  But you sacrifice 90% of the light when
you do this, so it's kind of a last resort for stars of the typical mag
(say 12-15) we study.

Fourth straight crystal clear night on Kitt Peak!  We've been going
dusk-to-dawn on HS2331+3905, a star truly wallowing in periods.

joe