(cba:news) yy dra, fs aur, wx pyx

Joe Patterson jop at astro.columbia.edu
Fri Jan 23 17:33:44 EST 2004

Dear CBAers,

Some new stars poppin' up and beggin' for attention.  YY Dra just jumped
into outburst, for the first time in 4 years.  It's a very rare
opportunity because YY Dra is a DQ Her star (rapidly rotating magnetic
white dwarf in a CV), and there is still not much understanding of how a
dwarf-nova outburst interacts with a magnetic field.  Past eruptions have
been short, so this is a time to jump to action NOW.  YY Dra is sometimes
known as DO Dra in variable-star catalogs, by the way (including cv cat as
I recall).  It should be about 12th mag now... though may fade soon.

The story on FS Aur is quite different.  This is a mystery star with a
photometric period much longer than its spectroscopic period.  From the
sparse 2003 coverage it looks like the period is changing now - and we
need some dense coverage now to document this change, before onrushing
twilight knocks us out.  The long period (3.5 hours) keeps the observing
season short (you kinda need to observe for a period, or nearly so).

Then there's WX Pyx.  This is a HARD target, at 17th magnitude.  But it
has a 26 minute signal of quite large amplitude, and many of you
australites can get good data on it when the nights's conditions are good.
Not pretty data, but of high scientific value.  Little is known of WX Pyx,
but if you hammer away on it for the next month, we can greatly increase
the world's knowledge of it, and properly define its DQ Her star

Happy observing out there!


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