Re: GSC 1040-399 + new variable

[Michael Koppelman <lolife@bitstream.net>]

On Wednesday, July 16, 2003, at 10:01 PM, Arne Henden wrote:

> Hmmm.  30th order polynomial?  You hardly have enough points
> to uniquely solve for such a beast, much less get a least-squares
> solution!

You'll have to talk to Grant Foster about that. It sure worked pretty 
well! I can show you a screen grab if you want.

>   67 minutes, 133 minutes, and 3 minutes are all commensurate to
> first order.  Since John indicates this is a 5arcsec double, I am
> more inclined to believe centroiding errors leading to flux
> "sloshing around" in your measuring aperture, perhaps depending on
> seeing variations.  Try using a much larger aperture to minimize
> centroiding problems and see if the variations decrease or stay the 
> same.

It's the regularity of the sloshing that strikes me as weird. For 5 
hours it oscillated almost precisely every 67 minutes. I will try 
larger apertures or PSF fitting and see what difference that makes.

Thanks!
Michael