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          THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS
               25 Birch Street, Cambridge, MA 02138 USA
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              AAVSO ALERT NOTICE 179 (December 14, 1993)


2337+56 NOVA CASSIOPEIAE 1993

Syuichi Nakano reports the photographic discovery of a nova in Cassiopeia 
by Kazuyoshi Kanatsu of Matsue, Shimane, Japan, on December 7.47 UT at 
photographic magnitude 6.5 on a T-Max 400 exposure with a 55mm f/2.8 lens.  
This discovery was confirmed by the discoverer on December 11.42 at 
photographic magnitude 6.5.  Other estimates include: Dec. 5.44 UT, <10.0 
(A. Tago, Tsuyama, Okayama, Japan; T-Max); 7.47, 7.5 (Tago); 11.63, 6.5 (S. 
Otomo, Kiyosato, Yamanishi, Japan, visual); 11.65, 6.4 (K. Tomita, Tokyo, 
Japan, visual) (IAU Circular 5902).

K. Kawanishi, Akou, Hyogo, Japan, has determined the 1950 position of 
N Cas 93:
 
               R.A. 23h 39m 22.36s    Dec. +57 degrees 14' 23.7" 

B. Skiff, Lowell Observatory, reports that a precursor candidate appears
on both the B and R plates of the Palomar Sky Survey at B magnitude 18 and 
B-R ~+1.0 (IAU Circular 5904).

Peter Collins (Scottsdale, AZ) reports an independent visual discovery of 
N Cas 93 on Dec 13.29 UT at magnitude 6.0, with a second observation on Dec 
13.40 at 6.2.  The nova has been around magnitude 6.5, as reported by 
observers around the world, and shown by the following recent observations:
Dec 14. 01 UT, 6.0 (G. Poyner, Birmingham, England); 14.12, 6.3 (R. Stewart, 
Rochelle Park, NJ); 14.15, 5.9 (C. Scovil, Stamford, CT); 14.18, 6.4 
(P. Schmeer, Bischmisheim, Germany); 14.22, 6.1 (W. Dillon, Missouri City, TX).
    
N Cas 93 is close to the Mira variable 2339+56 Z Cas.  The accompanying 
"b" chart of Z Cas, prepared by C. Scovil, shows Nova Cas 1993 together with 
comparison stars with photoelectric (V) magnitudes from Geneva Observatory 
(M. Grenon et al.) and Lowell Observatory (B. Skiff).  Please monitor this 
bright nova closely  and report your observations, indicating the comparison 
stars used, to AAVSO Headquarters using the charge-free number (800-642-3883).
The AAVSO answering machine is on nights and weekends for your convenience.

Our congratulations to Kazuyoshi Kanatsu and Peter Collins!


BRIGHTENING OF 0849+20 OJ 287 CNC

The BL Lac type quasar-like object OJ 287 Cnc, which has quasi-periodic 
brightenings every 11 to 12 years, may be starting to be active again, as 
indicated by the following observations reported by D. York, Abiquiu, NM, 
and G. Poyner, Birmingham, England: Dec. 9.24 UT, 14.6 visual magnitude (York);
10.25, 15.0 (York); 11.25, 15.0 (York); 14.03, 15.1 (Poyner); 14.26, 15.4 
(York).

Its last flaring activity was in 1983-84, when OJ 287 Cnc brightened to about 
magnitude 13.5.  There is an international campaign to monitor this object 
this winter.  Please observe it closely, using the accompanying "e" scale 
AAVSO preliminary chart, recording your observations to the minute (four 
decimal places of the day), and call in your observations to AAVSO 
Headquarters if you see OJ 287 Cnc brighter than magnitude 15.0. 


CLOSE MONITORING REQUESTED

1. 2138+43 SS Cyg.  Astronomers in Europe are interested in observing SS Cyg 
with the IUE satellite during its next anomalous outburst.  Please monitor SS 
Cyg closely, and inform AAVSO Headquarters when it starts to brighten, and 
then continue to report your observations of SS Cyg throughout the rise to 
maximum so we may determine if the outburst is anomalous and inform the 
interested colleagues. 

2. 0749+22 U Gem.  Astronomers at the Space Telescope Science Institute and
Villanova University are interested in monitoring the next outburst of U Gem 
with the EUVE satellite, and have asked our assistance.  Please monitor U Gem 
and report your observations to AAVSO Headquarters when you see it brighter 
than magnitude 13.  Please keep us informed of its behavior throughout its
outburst.

3. 2318+17 IP Peg.  Astronomers in the Canary Islands wish to be alerted to 
the next outburst of IP Peg.  Please monitor this star closely and inform us
when it brightens.  Please be advised that IP Peg is a cataclysmic variable
that has deep eclipses of two magnitudes or more with a period of 3.8 hours 
and lasting several tens of minutes.   Monitoring the eclipses during the 
outburst is valuable and recommended using the following ephemeris provided 
by P. Szkody: JD 2445616.4156 + 0.15820616E, and reporting the timing of all 
positive observations to the minute (four decimal places).

4. 0900-31 T Pyx.  Astronomers at the Space Telescope Science Institute have 
asked our assistance in alerting them immediately when T Pyx has its next 
outburst.  This recurrent nova, which has had outbursts in 1890, 1902, 1930,
and 1966, is overdue for an outburst.  Observers are cautioned to be certain 
of their identification of T Pyx.  Several times in the past, we have been 
alerted to the variability of numerous stars in the field, as indicated on
the accompanying chart from the Royal Astronomical Society of New Zealand.

5. 1834-23 V348 Sgr.  Observers are reminded to call in your observations
to AAVSO Headquarters when V348 Sgr begins to recover from its minimum so 
that we may inform astronomers at Louisiana State University, who are 
interested in monitoring it during its rise back to maximum.

Most sincere thanks for all your efforts throughout the year to provide data 
support to so many variable star research programs which use both ground-based 
telescopes and space satellites.  You play a vital part in these projects!

Happy holidays and good observing,


Janet A. Mattei
Director