Re: GSC 1040-399 + new variable

[Arne Henden <aah@nofs.navy.mil>]

Thomas Droege wrote:
> One of the uses of the tass data is to find good comparison stars.  Several
> of us are working to filter the tass data to find the stars that do not
> seem to vary.  In a way this might be as useful as the variable data.  ;^)
> 

You get that automatically, don't you?  If the star is not variable,
then by definition it is constant.
   As I have often cautioned people using my 1-2-3 night sequences, they
do not guard against variability of any particular star.  For the
Henden/Honeycutt sequence papers, we used Kent's Roboscope multiyear
dataset to check for variability and deleted any possible variables
from the sequences.
   Tom's multiyear (plus, of course, other Mark IV sites) datasets will
be useful in looking for the really long-term variations, such as
starspot activity like the solar cycle, or finding those year-plus
eclipsing systems.  The ROTSE dataset (when/if it becomes available)
will do the same.  The long-term variables (not Miras!) are an
uncharted regime in the all-sky sense (MACHO and OGLE amongst others
have multiyear datasets in small regions of the sky).
   The real benefit IMHO of survey work is not the common variable
like EBs, Miras or RR Lyrs, but the unusual star.  With many millions
of potential candidates, you can afford to ignore 99.999percent of
all stars and concentrate on a handful of interesting ones.  Let
someone else study the common stars; skim the cream.
Arne