(cba:news) GW Lib at last...

Joe Patterson jop at astro.columbia.edu
Thu Apr 12 09:55:31 EDT 2007

Dear CBAers,

Rod Stubbings just reported that GW Lib, practically dormant since 1983, 
is in outburst at 13.8.  GW Lib had at least one previous short 
outburst, and that's probably what this is.  But it may also be the 
beginning of a superoutburst... and if so, it's tremendously important.
And well placed in the sky too!  At -25 degrees, it's even marginally 
available for southern USA observers.

So it's absolute top priority now for (nearly) all observers, and worth 
staying on until it arrives back at minimum (V=16.6, although catalogues 
tend to assign it an incorrect V=18.5).  That might come in just a few 
days; or it could well be a few months!  Even if it's just a short 
outburst, it's still quite interesting: the only previous coverage of 
short outbursts is a single image.

Here's Rod's message...


Gw Lib is in outburst.

LIBGW          070411.509  <157  Stu.RASNZ
LIBGW          070412.494   138  Stu.RASNZ

Rod Stubbings

Re other objects, it's time to DROP DT Oct.  YY Sex, AM CVn, and CR Boo 
remain good targets.  BZ UMa went into outburst a few days ago, and 
CBAers jumped to attention pretty fast.  I'm kinda torn about it.  It's 
true that BZ UMa is a strange star that stands well apart from other CVs 
of short Porb; that makes it a very tempting target, very desirable for 
study.  On the other hand, we've gotten good coverage of a previous 
outburst, and the star exhibited mainly erratic variability.  So that's 
one excellent reason to study it, and one fair reason not to.  Excellent 
trumps fair, so I guess it's a good evening target for you borealites.
I'll study the data and comment again soon.

Actually, I don't think I've received any yet.  Can you send me the BZ 
UMa data?

Happy observing!  We're in a major extension of winter here in the 
Northeast USA.  Decently clear nights... but I didn't think I signed up 
for all this springtime cold.


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