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          THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS
               25 Birch Street, Cambridge, MA 02138 USA
                BITNET:  aavso@cfa     SPAN:  cfa::aavso
                    INTERNET:  aavso@cfa.harvard.edu
               Tel. 617-354-0484       FAX 617-354-0665


                 AAVSO ALERT NOTICE 193 (September 29, 1994)


OUTBURST OF CATACLYSMIC VARIABLE 2325+43 DX ANDROMEDAE

We have been informed by Tonny Vanmunster, Landen, Belgium (Belgian 
Astronomical Society, VVS, Cataclysmic Variable Circular (CVC) 17), Guy Hurst, 
Basingstoke, England, (The Astronomer (TA) E886),  and AAVSO observers in the 
United States that the dwarf nova type cataclysmic variable DX And is 
undergoing an outburst, as indicated by the following observations:

Sep 23.833 UT, 12.6, T. Vanmunster, Landen, Belgium (via CVC); 23.872, 12.3, 
J. Pietz, Erftstadts, Germany (via CVC); 24.810, 12.2, M. Westlund, Uppsala, 
Sweden (via TA); 27.067, 11.7, J. Nordby, Moorhead, MN; 28.081, 11.8, R. 
Stewart, Rochelle Park, NJ; 28.195, 11.6, J. McKenna, Upper Montclair, NJ; 
29.127, 11.6, Stewart; 29.211, 12.1, McKenna; 29.300, 12.1, Nordby; 29.375,
12.0, W. Albrecht, Pahala, HI.

The most recent outbursts of this cataclysmic variable occurred in August 
1993, when DX And reached magnitude 10.7 at maximum (Tonny Vanmunster was the 
first observer to detect the start of this outburst), and in February 1992, 
when it reached magnitude 11.6.  The outbursts generally last two to three 
weeks.  

Please monitor the current outburst of DX And closely, using the accompanying
finder chart, and report your observations to AAVSO Headquarters.  


2027+52 V1974 CYGNI = NOVA CYGNI 1992

We have been informed via VSNET in Japan that Brian Skiff, Lowell Observatory, 
has provided faint photoelectric magnitudes for the field of N Cyg 92 = V1974 
Cyg.  These magnitudes are for the comparison stars marked 13.4 and 14.5 on 
the accompanying finder chart.  The 13.4 was measured by Skiff last year at 
V=13.42; we have kept the magnitude at 13.4 for homogeneity of observations.
The 145 extends the sequence photoelectrically.  Also, early in 1994, Charles 
Scovil obtained a photovisual sequence by measuring the plates of V1974 Cyg; 
his photovisual sequence was not widely distributed at the time, but is 
incorporated into the accompanying chart.  We welcome comments from observers 
as to how the 14.2 photovisual, 14.5 photoelectric, and 15.0 photovisual fit 
together, and also how they match the brighter end of the sequence.  It is 
interesting and encouraging to note that Scovil obtained the same photovisual 
magnitude (i.e., 14.5) for the 14.5 comparison star that Skiff measured 
photoelectrically.  Please indicate the comparison stars you used when making 
brightness estimates of V1974 Cyg.


REQUEST TO MONITOR CATACLYSMIC VARIABLES FOR THE HUBBLE SPACE TELESCOPE (HST)
AND INTERNATIONAL ULTRAVIOLET EXPLORER (IUE)

A. HST

Please monitor the following cataclysmic variables that will be in the 
observing program of HST in October:

Desig     Name    Type        Present brightness  Scheduled observation 
0201+14   TT Ari  Dwarf nova  10.5                Oct  7 11:00 - 17:44 UT
2318+17   IP Peg  Dwarf nova  11.8 - 15.3-15.8    Oct  8 13:50 - 16:20 UT 
2318+17   IP Peg                                  Oct  9 01:05 - 03:38 UT
1843+00 V603 Aql  Nova 1918   11.4                Oct 12 05:00 - 11:30 UT

B. IUE

We have a standing request from astronomers at the VILSPA Station of the IUE 
in Spain to be alerted to activity in the stars described below, as they plan 
to observe these objects with the IUE when the circumstances are appropriate:

2138+43 SS CYGNI.  Please notify us of the outburst of SS Cyg in case the 
outburst should be an anomalous one, that is, a symmetrical outburst in which 
the rise is slow.

1813+49 AM HERCULIS.  Please monitor this cataclysmic variable closely 
whenever possible and call your observations in to AAVSO Headquarters when it 
begins to fade to its down state.


OUTBURST OF 1439+22A UZ BOOTIS

Our sincere thanks to those observers who monitored the recent rare outburst 
of UZ Boo.  An interesting feature of the outburst was that immediately after 
the star faded, it briefly brightened again.  Presently, we are studying the 
outburst behavior of UZ Boo, including this unusual behavior.  Checking our 
database, we find that brightening right after outburst is not unprecedented 
for UZ Boo - there is an observation made by C. Scovil of the 1978 outburst 
which indicates that the star may have brightened immediately after it faded.


UPDATES ON A FEW SOUTHERN R CORONAE BOREALIS TYPE VARIABLES

Danie Overbeek, Edenvale, South Africa, informs us that the following Southern
hemisphere R CrB stars are fading:

1834-23 V348 SAGITTARII - Aug 29.8 UT, 13.2; 30.7, 13.2; 31.7, 13.3; 
Sep 1.7, 13.2; 2.7, 13.2; 3.7, 13.2; 4.7, <13.4; 5.7, <13.1; 6.7, <13.4; 
7.7, <13.4; 9.7, <13.4.

1428-39 V854 CENTAURI - Aug 30.7 UT, 10.2; 31.7, 10.6; Sep 1.7, 10.8; 
2.7, 11.4; 3.7, 12.0; 4.7, 12.7; 5.7, 12.8; 6.7, 12.9; 7.7, <13.0; 9.7, <13.0.

D. Overbeek also informs us that RZ Nor, which had been at maximum at around 
magnitude 11 until September 11, has also started to fade, and provides us 
with the following observations:  Sep 11.7 UT, 11.2; 14.7, 11.8; 15.7, 12.0; 
16.7, 12.3; 18.7, 12.5; 19.7, 12.7.

OUTBURST OF 2209+12 RU PEGASI

We have just been informed that the dwarf nova cataclysmic variable RU Peg
is in outburst.  Most recently, RU Peg has had two faint outbursts, one in 
May 1994 when it reached magnitude 11.4, and one in June 1994 when it reached 
magnitude 11.6.  Current observations include: Sep 29.153 UT, 11.4, W. Dillon,
Missouri City, TX; 29.205, 11.2, J. McKenna, Upper Montclair, NJ; 29.370, 
11.8, W. Albrecht, Pahala, HI.  


The answering machine at Headquarters, with our charge free number 
(1-800-642-3883), is on nights and weekends for your convenience.  

Many thanks for your dedicated efforts and valuable observations.

Clear skies,

Janet A. Mattei
Director

Keywords:
AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484