(cba:news) oy car, and aas meeting
jop at astro.columbia.edu
Mon Mar 27 07:29:51 EST 2000
Mostly southern talk first. I've studied the V803 Cen data sent in so
far, and concur with Stan: the star is now in its cycling state, with a
period that is perhaps slightly shorter than in 1997 (20 hr versus 23 hr).
This far off resonance with the 24-hour cycle of our home planet, there's
a tendency to see "outbursts" where the reality is just little maxima of a
This describes data furnished by Robert Rea, Maria Marsh, Fred Velthius,
and Jennie McCormick, during JD 625-629. But it's likely (not absolutely
certain) that the earlier rise was V803 Cen's version of a superoutburst -
a pretty quick affair (3-4 days long) with no important cycling within it.
Stan, do you agree with this? (I haven't seen your data yet, and they may
well establish or refute this). Small 1610 s superhumps punctuated that
625-629 data, but I was hoping for the big humps that we saw only once -
in 1992. They woulda been slightly earlier. Any coverage slightly
The possibly shorter period is definitely of interest now, so it's a good
target for continued coverage.
OY Car is back at minimum now, but I've studied the data closely and it
supplies a wonderful record of superhump and eclipse changes in a dwarf
nova. It shows by far the clearest sign of an elliptical disk, in the
oscillation of the time of mid-eclipse. I'm writing it up now for
publication. Since most of the contributing observers are somewhat new
to our network, I'd like to include some detail about each person's
telescope, observatory, observing procedure, detector, and data analysis
procedure. And about the people too, though that part probably won't
get through the editor into the scientific paper. Can you send me such
Some of this I'd like to exhibit at the AAS meeting in Rochester on June
5. I hadn't realized this till an hour ago, but there will evidently be
a day on (nominally) professional-amateur collaboration in astronomy.
I'll certainly be there, and I hope to convince some of you to come too.
There will I believe be a minor-planet (you know, the killer variety)
conference at or near Alfred University just afterwards, which John
Stull and Gordon Garradd must know all about. John or Gordon, could you
let us know?
In the north, DW UMa remains the best target. In the south, v803 Cen
and BR Lupi. The latter is kind of a fishing expedition, but I know
from my correspondence that some of you like fishing. And so do I.
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