(cba:news) stars for spetember
jop at astro.columbia.edu
Sun Sep 6 09:51:21 EDT 2009
Those pesky dwarf novae are taking a little rest (apparently V713 Cep
didn't have real serious intentions), the bright Moon is soon to leave
us, and it's a good time to ramp up observing a bit. In particular,
it's vital that we now get a couple of September weeks on V4743 Sgr, a
star we tracked extensively in June and July. By adding September
coverage, we accumulate a total of ~120 days of seasonal coverage - this
gives us enough baseline to count cycles uniquely all the way back to
2003, and thus establish a precise ephemeris for both the orbital and
the (presumed) rotational clocks. That's the really high priority for
BW Scl is, too. We have about two uninterrupted weeks now, due to Berto
and Bob Rea. Around one more should yield a power-spectrum sensitivity
almost as good as we could ever theoretically obtain. So let's keep the
faith a little longer.
Aside from these two, the other southern star I recommend is VZ Scl.
We've never done a serious campaign on it, and with the star decently
bright at 15.6, it's time to train some telescopes on it. I suspect
this maybe be a long-term target.
Northern observers have been a little quiet lately. Maybe the beach has
been too tempting. But when you get back from the beach, V455 And
awaits. That's my number one recommendation - very long runs on this
well-placed star. Shorter runs on RX0022+61 = IGR0023+61, RX1803+40,
and RX1703-05 would also be good.
Finally, an excellent beginner star is V Sge. Plenty bright, and with
deep eclipses which show a period change still not understood (and not
so securely measured). Also, it's pretty easy for me to evaluate data
quality for this star. Same goes for AO Psc and FO Aqr; these don't
need any new coverage until December, but they're easy to observe and
will help me evaluate data-quality issues.
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