(cba:news) BW Scl and V455 And, mainly

Joe Patterson jop at astro.columbia.edu
Mon Aug 24 10:11:27 EDT 2009

Dear CBAers,

The dwarf novae of mid-August have dropped off the radar. We managed to 
track some of 'em (1610+09 and 2230-14), while others (2100+00) were 
just too faint.  Wipe 'em out.

The prime southern object for the next few weeks should be BW Scl = 
RX2353-38.  This object is about V=16.5, but it has large-amplitude 
signals at the orbital and one other frequency (of unknown origin)... 
plus a superhump signal that pops up every so often, not associated with 
any outburst.  In fact, no outburst has ever been observed from this 
star.  It is one of the burned-out CVs which has been a major topic of 
research in recent years - sometimes called the WZ Sagittae stars.  We 
manage to do very well with this star - make it a regular feature of 
your August and September nights!

In the north, the bookended star is V455 And = HS2331+39.  Practically 
everything I just wrote applies to this star also!  Except that one 
outburst finally did occur, in 2007.  It's now just a tad above 
quiescence at 16.5, but has some very strong periodic signals, and will 
greatly reward your time.  We expect to have some time also at 
professional telescopes (SAAO and KPNO) during the next week on both 
stars, so that will boost the value of the global coverage.

The DQ Her stars remain valuable, except V1223 Sgr, which has had enough 
coverage to pin down the period change.  Especially RX1803+40=Her, 
RX0022+61=IGR0023+61=Cas... and AO Psc and FO Aqr as the easy bright 
targets.  The latter two are the ideal targets for people starting out 
in this enterprise (of which we have several this month).

Finally, a meetings reminder.  We'll meet again in Big Bear along with 
SAS (the astro club, not the airline) in late May 2010.  It's possible 
we'll have a small session of our own, so people can give talks about 
their own setup - not just the big more scientifically oriented talks 
which are the main element of the meeting.  In addition, there's a AAS 
meeting in Boston in late May 2011, where there's likely to be a pro-am 
research section where we - and more importantly, individual CBAers - 
could play a role and meet each other.  In both cases, I promise to 
organize some social functions outside the confines of the meeting (and 
not just golf).

Happy observing!


More information about the cba-public mailing list