[vsnet-chat 1340] Re: Designation of new variable stars

[aah@nofs.navy.mil]

Brian and Taichi have given a good dialog on variable star designations.  While Brian feels
6arcsec resolution is sufficient for a coordinate grid, I agree with Kato-san when it
comes to Milky Way fields or external galaxies.  Since everyone seems to have the GSC or
USNO-A and a program like Astrometrica, it seems silly in the current age to not go ahead
and expand the scheme to the nearest arcsec.  That, at least, handles almost all
ground-based cases.

Note that many programs (Hipparcos for example) have gone to a decimal degree format
in both coordinates.  Since we are discussing a naming scheme that may be used for
many years in the future, perhaps we should consider such coordinates instead.  In
addition, the ICRS is more-or-less J2000 Equinox, so we don't need to include an equinox
designator if ICRS is used.

I disagree with Taichi regarding a unique designator for variable stars.  I would prefer
a single designation scheme for ALL objects, since there always cases where an object
is found to be variable after it is cataloged for some other purpose.  Using a unique
scheme also removes the difficulty of a preliminary designation that later proves to
be false.  The star remains; just its variability 'flag' is removed.

I confess we just used a running index for the FASTT variables because of that
scheme's convenience.  I will make an effort to use an ra/dec scheme in the next paper!

Arne

VSNET Home Page

Return to Daisaku Nogami

---

vsnet-adm@kusastro.kyoto-u.ac.jp