(cba:news) Stars for February

Joe Patterson jop at astro.columbia.edu
Tue Feb 1 22:17:36 EST 2011


Dear CBAers,

Sorry for my prolonged silence.  Suddenly, actual students have arrived 
back at school!

And I'm grateful for all the leadership you guys have shown with respect 
to the various stars popping off up there.  The dwarf novae have been 
really putting on a show... and led by Enrique and Tom, the coverage has 
been just outstanding.  I'm still sorting 'em out, but it does look like 
V1212 Tau and CSS0431-03 will be having a significant impact on 
dwarf-nova studies - a tad out of the ordinary.  And ER UMa is even more 
interesting, oddly flashing very strong negative superhumps at us.  That 
one shocked me.  I've always wanted to do a long study of ER UMa, since 
it offers the opportunity to follow the variations throughout an entire 
outburst cycle.  But never got around to it.  Now, the star cries out 
for attention... and it's definitely UMa season!  So fire away on ER.

Unfortunately, I have another UMa star, and another almost-UMa star, to 
promote.  The first is UMa 6 (Downes designation, also known as 
4U0928+50). This is a 10.04 hour eclipsing binary, with still no proper 
publication on it.  We need to get about another 5-8 nights on it to 
complete our study.  Not a really big project, but the runs need to be 
long since Porb is.  The second is BH Lyn - another eclipsing CV which 
we studied in the mid-90s and never got back to.  It has pretty good 
superhumps, but the coverage back in 1996-7 was sufficiently sparse that 
I couldn't actually distinguish - due to aliasing - positive from 
negative (i.e. suoerhumps).  It should be a snap with long time series 
from Europe and North America spliced.

The DQ Her stars - and I'm embarrassed to be so fond of them when the 
dwarf novae are flashing such beautiful fireworks - can take a break for
a couple months.  Though a coupla runs on HT Cam would be nice.

In the south, we need to pick up XMM 1151-6237 again, now that it has 
decently come out of the Sun.  Enough to get the first 2011 timings and 
spruce up the ephemeris.  And another 5-6 runs on T Pyx (thanks, Bob!). 
  But the main southern target I want to promote is CP Puppis. This is 
another star I've been wanting to get back to for 15 years; something 
always comes up!  But let's do it in 2011 once and for all. And by the 
way, observers in the southern USA can usefully contribute to this one 
too - I'm hoping for NZ-AU-South Africa-USA.

Finally, an update on AAVSO/AAS.  I heard from some of you expressing 
your intention to attend, and others planning on Big Bear instead 
(granted: cheaper, better weather, beautiful surroundings, closer to our 
largest contingent, and an always-great meeting).  So our little band 
will be divided, and any "CBA meeting" will wait another year.  But I'm 
still promoting the AAVSO/AAS meeting!  If you're planning to attend, 
remember to join the AAVSO first, since that'll get you into the AAVSO 
meeting and a serious discount on the AAS registration (which is hefty). 
  I'll soon send out some suggested hotel information in Boston.  See 
the AAVSO website for this May 21-26 joint meeting.

joe



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