(cba:news) may-june targets
jop at astro.columbia.edu
Sat May 29 23:34:14 EDT 2010
Well, EX Hya went like a tornado, as is its wont. And V1032 Oph has
long since faded. And it's time to draw the curtain on CR Boo. So
let's switch to a new menu for June.
The erupting and eclipsing dwarf nova in Lynx ("Lyn" in Downes catalog,
or SDSS0903+33) would be a great target for about one more week.
Enrique de Miguel has been fighting alone on this one; he has found
excellent superhumps - now we need some USA coverage to nail down the
period precisely! Not in the sky long - you can close the telescope in
time for the late news!
The new dwarf nova in Pegasus (OT2138) will remain interesting as long
as it's bright enough to observe. Not very well placed of course... and
of course the undesired companion star will get annoying as the star
fades. But we manage to do OK with splices from Spain and New Mexico,
among others. So we're managing to keep decent track of the evolving
outburst. Lots of room for improvement there!
I've received several runs now on SDSS1339+48, a CV with a pulsating
white dwarf. To my delight, Bill Goff is able to detect these
pulsations with a 14-inch telescope - even with a dead-full moon in the
sky! So we can find 2% signals on V=17.5 stars in full moon - verry,
verry nice. This star is worth tracking a few weeks, or until it
proves/disproves its basic coherence.
An even better target of the same ilk is GW Lib, and I really HOPE that
some North American observers - as well as our usual stalwarts in
ZA/AU/NZ - can contribute to this star's record. I promise to analyze
the data immediately and comment. The pulsations may or may not be
present, but the other main target is the 2.1/4.2 hr variation that has
become slightly famous - and remains unexplained.
So far, no takers on V4743 Sgr. We have quite good coverage on it
through last year - just need a few more timings to conclude the study.
Well placed for you australites.
The bright northern target this season is V1084 Her (= "Her" in Downes
catalog). We started it last month, then the dwarf novae started
popping off. Time to go back into the water. Also, a target I highly
recommend in the post-midnight sky is GD 552 (= Cep 1). I'd love to
start the GD 552 season about now (and Helena will get 1-2 runs with the
Finally, there's GD 552 = Cep 1. Available to northerners after 1 a.m.
Let's begin the GD 552 observing season!
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