AAVSO ALERT NOTICE 329 (November 22, 2005)
Date 23/11/2005 10:33:45 | Sujet : news en anglais
| SUBJECT: 1815+50 DV DRACONIS - RARE OUTBURST
Object: 1815+50 DV DRA
Coordinates: R.A. 18h 17m 23.07s Decl. +50o 48' 17.7" (J2000.0)
The possible WZ Sge-type cataclysmic variable is in outburst, according to
observations reported by Tim Parson, Forest Lake, MN, and Patrick Schmeer,
Bischmisheim, Germany. Schmeer reports ([AAVSO-photometry]) this
observation is only the second recorded outburst of DV Dra; its first one
was a superoutburst in June 1984, when the star reached photographic
magnitude 15.1 (IBVS No. 3626). No outbursts are recorded in the AAVSO
International Database since DV Dra was added in 1994.
DV Dra is faint and near the sun, so it is a difficult target for visual
observers, however, visual observations are welcomed. CCD observers are
urged to conduct V-band time series photometry, keeping the runs as long
as possible, and the exposures as short as possible with S/N ratio = 20 or
better.
Charts: AAVSO 'e' and 'f' scale charts for DV Dra may be found at:
http://www.aavso.org/cgi-bin/searchcharts3.pl?name=DV%20DRA
These charts may also be requested from AAVSO Headquarters.
Note that on the 'f' chart, DV Dra is misidentified. DV Dra is actually 15
arcsec west of the star marked on the chart as DV. DV Dra may be
unambiguously identified on the Downes et al. finding chart at
http://icarus.stsci.edu/~downes/cvcat/
Report Object to the AAVSO as: 1815+50 DV DRA
Observations Reported to the AAVSO: Nov. 04.7819 UT, <16.1, C. Jones, West
Hanningfield, Essex, England; 06.7960, <15.0, G. Poyner, Birmingham,
England; 08.0493, <15.0, M. Simonsen, Imlay City, MI; 09.8020, <15.0,
Poyner; 15.0650, <17.5 CR, P. Schmeer, Bischmisheim, Germany; 15.0650,
<17.5 CR, Schmeer; 16.8110, <15.0, Poyner; 17.0670, <18.0 CR, Schmeer;
18.0640, <17.2 CR, Schmeer; 18.8320, <15.0, Poyner; 19.0640, <18.0 CR,
Schmeer; 20.0028, <15.0, Simonsen; 21.0639, 14.9, T. Parson, Forest Lake,
MN; 22.0620, 15.1 CR, Schmeer.
Congratulations to Tim and Patrick on their independent discoveries of
this rare outburst!
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