(cba:news) stars for mid-June
jop at astro.columbia.edu
Tue Jun 15 22:51:41 EDT 2004
Time for major changes in CBA targets.
V380 Oph coverage should be called off. The observations have been great,
and show that there is some kind of negative superhump present. But that's
well established by the data so far - and because the superhump is not
very stable, increased coverage doesn't significantly improve the science.
So time to move on.
V803 Cen DID, as reported before, rise from its quiescent magnitude around
16.5. But it didn't get quite to its full level of 12.9, and failed to
grow new superhumps. That may be only a few days away, though. So we
should keep an eye on it, and cover it intensively if it rises to full
For northern observers, I recommend two new stars in Hercules: V849 Her
and V825 Her. Fairly obscure CVs, probably novalikes, candidate for
orbital or superhump periodicity - and bright enough for CBAers, at least
normally. Plus one other star, V1494 Aql - that very bright nova that
went off in December 1999.
For southern observers, I recommend novae in Sagittarius. I am not
exactly sure of the best choices, and some of you might want to pipe up
here since I know some of you keep close watch on these things. Anyway,
here they are: V4633 Sgr, V4745 Sgr, V4743 Sgr, and V4744 Sgr. The first
and the third have roughly known periods (about 3 and 7 hours), and
corresponding periodic signals. Both are likely to be rewarding targets.
The other two are pretty much terra incognita. The other nova, good for
south and north and any other hemisphere you might know about, is V1494
That's it. Pretty much a clean slate. I expect to do a much better job
getting all these studies into print now, as classes have ended and I have
a year's sabbatical stretching in front of me!
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