(cba:news) U Sco, KT Eri, Swifties, SDSS1507+52 = Boo

Joe Patterson jop at astro.columbia.edu
Sun Feb 7 08:21:19 EST 2010

Dear CBAers,

Some new targets for the menu.  First, just to ratify/cheer Brad 
Schaefer's exhortations re U Sco.  Just obtain the longest feasible time 
series from nova-rise till dawn, and continue till the end of February. 
  Nuff said.

The other fancy nova in this month's sky is KT Eri = Nova Eri 2009.  The 
expected strong soft X-rays finally showed up, and they're pulsed with a 
35 second period (or maybe quasi).  So this is a nice target for an 
evening look-see, perhaps especially at high time resolution to see if 
any of that fast activity occurs at visual wavelengths. (Long shot, but 
plenty worth looking).

Two good X-ray targets are well-placed in the February sky.  There's Big 
Swifty, at 07 46 17.12  -16 11 27.9... a 13.6 mag star very likely to 
flash some quite strong periodic signals.  Well placed for all!

And there's Little Swifty, at 04 57 08.3  +45 27 50.  Same basic story 
(Swift X-ray source identified with a CV, and with a spectrum suggesting 
probable DQ Her status).  Needs only some nice light curve to test the 
hypothesis and reveal the period.  This one's fainter, I think near 17 
but I'm not sure.

Somewhere in the window Feb 15-18, the Hubble Telescope will execute our 
proposal for an ultraviolet spectrum of SDSS 1507+52 = Boo.  To carry 
this out on schedule, we need to certify that the star is at quiescence, 
around V=18.  Apparently the detectors may fry if the star erupts - 
which it never has... but then again, history is just the series of 
extremely unlikely events, one after another.  So can you spy on this 
star and see if it's up to any mischief?

Info on the Swifties coming up shortly...


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