[vsnet-alert 178] AAVSO ON WORLD WIDE WEB

[Janet Mattei <jmattei@aavso.org>]

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

                AAVSO ALERT NOTICE 211 (August 1, 1995)

AAVSO ON WORLD WIDE WEB

We are proud to announce that the AAVSO now has a home page available on the
World Wide Web (WWW).  The address of our home page on the WWW is:

                   http://vsnet.aavso.org

Point your browser at this address for information on the AAVSO, variable stars,
Alert Notices and other Publications, sample light curves and many more. We
will be updating our web page periodically, and including finder charts and
new light curves.  We invite you to visit the AAVSO home page frequently.
Soon, for each light curve we put on our web page, we will be listing the
names of the contributing observers, so visit our home page and see if you
are one of those observers!  For best results, we suggest that you use
Netscape 1.1 to view the page.  We welcome comments, suggestions, input, etc.
Please send mail to webmaster@aavso.org.

1958+56 V1028 CYGNI IN OUTBURST

We have been informed by our observers T. Burrows, Novato, CA, and D. York,
Abiquiu, NM, that they have independently observed the outburst of V1028 Cyg.
We were also informed via vsnet that J. Pietz, Erftstadts, Germany,
independently observed this outburst.  Below are recent observations of
V1028 Cyg:

Jul 25.010 UT, <14.0, E. Broens, Mol, Belgium; 25.994, <13.9, G. Poyner,
Birmingham, England; 26.2521, <14.0, T. Burrows, Novato, CA; 27.1563, <16.0,
D. York, Abiquiu, NM; 27.2542, <14.0, Burrows; 27.2549, <14.0, Burrows; 28.1868,
13.5, York; 28.2347, 13.5, York; 28.2625, 13.7, Burrows; 28.967, 12.7, J. Pietz,
Erftstadts, Germany; 29.1486, 12.7, York; 29.1667, 12.7, York; 29.2174, 12.7,
York; 29.911, 12.9, L. Szentasko, Budapest, Hungary; 29.913, 13.0, Vanmunster;
30.2104, 13.3, J. Griese, Stamford, CT; 30.216, 13.1, J. McKenna, Upper
Montclair, NJ; 30.2542, 13.0, R. Stewart, Fairlawn, NJ; 30.2764, 13.0, Burrows;
30.87, 12.9, Szentasko; 30.914, 12.7, Broens; 31.1319, 12.9, Stewart; 31.1875,
13.0, McKenna; 31.2549, 13.0, Burrows; 31.3368, 13.3, C. Scovil, Stamford, CT;
Aug 1.08, 13.5, G. Dyck, Assonet, MA; 1.1889, 12.8, McKenna; 1.1458, 13.0, York;
1.1944, 12.9, York; 1.2111, 13.4, Griese; 1.250, 13.0, Burrows.

V1028 Cyg has been closely monitored by the AAVSO since 1981.  Although it is
classified as an SS Cyg-type dwarf nova in the fourth edition of the General
Catalogue of Variable Stars, and also in the Catalogue and Atlas of Cataclysmic
Variables by Downes and Shara (Publ. Astron. Soc. Pacific, 105, 127; 1993),
the observations in the AAVSO International Database suggest that it may be
an SU UMa-type dwarf nova.  It has had several short and faint outbursts that
lasted from one to four days and reached maximum magnitude between 13.5 and
14.4.  It has also had one long outburst that was well-observed, in September
1992 - it began on September 5, reached maximum magnitude of 12.8 on the 6th,
and was brighter than 14.2 until the September 16. This outburst was the last
confirmed one observed of this dwarf nova until the present one, and it may
have been a superoutburst.

The fact that this current outburst is bright suggests that it may also be a
superoutburst.  In fact, Dr. T. Kato and the Ouda Team of astronomers in Japan
who have been observing V1028 Cyg since 29 July reported via vsnet that
the outburst light curve initially showed "very low amplitude (0.04 - 0.03
magnitude, alternately) double wave".  Their CCD photometry on July 30th
indicated that 'true' superhumps with single-peak hump structure had developed.
Their CCD photometry on July 31 showed typical superhumps with 0.29 magnitude
of amplitude and 0.063 day of period.  Thus, these observations confirm the
suggestion we have made, studying the AAVSO light curves, that V1028 Cyg is
an SU UMa-type dwarf nova.

Accompanying are "d" and "e" scale AAVSO preliminary charts for V1028 Cyg
prepared by C. Scovil, using the visual sequence from Wayne Lowder that was on
the earlier AAVSO V1028 Cyg chart, for consistency, and a CCD(V) sequence from
Kato et al. (Kyoto University), to extend the sequence.  We recommend that
observers use these charts in making observations, and indicate the comparison
stars used when reporting the observations.

We strongly recommend that visual and, particularly, CCD observers, observe the
superhumps by monitoring this star every three minutes for as long as possible
during the night, throughout the this superoutburst.  Continue your nightly
observations even after the outburst to detect possible brightening.  Please
record the exact time of the your observations to four decimals of the day.

Our sincere congratulations to Tom Burrows, Dave York, and Joachim Pietz for
"catching" this outburst so early and to Dr. Kato and the Ouda Team for their
excellent CCD photometry of this superoutburst.

BRIGHTENING OF 1601+67 AG DRACONIS

The symbiotic star AG Dra has started to brighten slowly, as indicated by the
accompanying light curve.  The list of observers contributing to this light
curve is given at the end of this Alert Notice.  It may be seen by this light
curve that the last outburst of AG Dra started at the end of May 1994, and
reached maximum at average magnitude 8.3 by the end of July 1994.

Accompanying are "b" and "d" scale AAVSO charts of AG Dra.  Please monitor AG
Dra closely, and report your observations, specifically stating the source and
the date of the chart, and the comparison stars you have used.

0409-71 VW HYDRI OBSERVED WITH EUVE

Excellent EUV data were obtained of the recent outburst of VW Hyi with the EUVE
satellite!  On July 7, W. Liller, D. Overbeek, and J. Hers telephoned to
inform us that the predicted outburst had started.  The EUVE Deputy Project
Scientist was able to start the observations with the EUVE 3 hours and 43
minutes after our notification that VW Hyi had gone into outburst!  The
satellite observed VW Hyi continuously until July 18, and obtained fantastic
and unprecedented data of the outburst and of the quiescence.  The EUVE data
indicate clearly that the outburst in EUV started about 0.5 day after the
optical outburst.  In addition to EUVE, the satellite Voyager observed VW Hyi
simultaneously.

Thus, during this short outburst that lasted only three days, this star was
observed from 80 to 350 Angstroms with EUVE and from 912 to 1150 Angstroms with
Voyager, in addition to the optical wavelengths by our visual and CCD observers.
These simultaneous observations are important in studying the flux produced in
the boundary layer between the disk and the surface of the white dwarf, the
inner disk, and the outer disk, respectively.  These measurements are also
important in understanding the mechanism that causes the outbursts.

We thank Bill Liller, Jan Hers, Danie Overbeek, Jan Smit, and observers of the
Royal Astronomical Society of New Zealand whose observations were transmitted to
us by their Director, Dr. Frank Bateson, for their very close monitoring and
their early alerts of the outburst.  Their observations and the timely and rapid
response by the EUVE team produced wonderful results!

As the second part of this project, the EUVE satellite will be observing VW Hyi
again in the middle of August.  A plea to our Southern Hemisphere observers -
please continue to observe this star closely, and continue to send in your
observations, and alert us immediately again when VW Hyi goes into another short
outburst, expected to occur soon.

REMINDERS - GK PERSEI AND T PYXIDIS

0324+43 GK Persei.  The old nova GK Per, that now has minor outbursts, is
scheduled to be observed with the XTE satellite as soon as it starts to
brighten.  We have a standing request to keep a close eye on GK Per and inform
astronomers in different parts of the world when it starts to brighten.  The
last minor brightening of GK Per was in July 1992, when it reached magnitude
10.3.  Please inform us when GK Per becomes brighter than magnitude 12.8.
Please use the accompanying "e" and "f" scale AAVSO charts to observe GK Per.

0900-31 T Pyxidis.  The standing request from astronomers at the Space Telescope
Science Institute to keep a very close eye on T Pyx continues.  We have been
asked to inform them, immediately, at any time of the day, when it goes into
outburst.  The last outburst of T Pyx occurred in 1966, when it reached
magnitude 7.2.  We remind observers that there is a star close to T Pyx to the
southwest; observers are thus urged to be extremely careful of their
identification of T Pyx.  Please use the "d" scale chart issued with AAVSO Alert
Notice 179 to observe T Pyx.

CHARTS AVAILABLE ON AAVSO FTP SITE

We have prepared electronic copies of AAVSO charts mentioned in this Alert
Notice for the following stars:  V1028 Cyg, AG Dra, GK Per.  They are available
from our FTP site:
                  ftp.aavso.org (198.116.78.2), in /pub/alert211


The answering machine at AAVSO Headquarters is on nights and weekends for your
convenience.  Please call our charge-free number (800-642-3883) to report your
observations.  We also encourage observers to send observations by fax to
617-354-0665 or by e-mail through the Internet to observations@aavso.org.

When telephoning in observations, please state the name of the star, the
magnitude, and the time of the observation.  Please speak clearly.  The
preferred time is either your local time (be sure to state the time zone and
whether it is Standard or Daylight Savings Time) or Universal Time.  You do
not need to give the designation of the star.   Please also include the
comparison stars you have used in making the observation.

Many thanks for your significant astronomical observations and efforts.

Good observing!

Janet A. Mattei
Director


AAVSO Observers of AG Dra in light curve shown in AAVSO Alert Notice 211:

M. ADAMS, A. BARANSKI, T. BENNER, A. BERVALD, N. BIGARRE, J. BORTLE, R. BOUMA, 
E. BROENS, C. BRUHN, T. BURROWS, F. CAMPOS, P. COLLINS, G. COMELLO, M. CSUKAS, 
C. CUBILLO, A. DIEPVENS, G. DYCK, C. FAUSEL, H. FEIJTH, R. FIDRICH, O. GABZO, 
J. GENSLER, B. GRANSLO, G. GUBBELS, C. HADHAZI, T. HAGER, E. HALBACH, 
G. HANSON, B. HASSFORTHER, L. HIETT, G. HURST, J. ISLES, L. JENSEN, L. KISS, 
A. KOCSIS, M. KOMOROUS, A. KOSA-KISS, W. KRIEBEL, G. KRISCH, T. LANGE, 
A. LAUVSTAD, J. LOVETT, P. MAURER, G. MAVROFRIDIS, J. MCKENNA, K. MEDWAY, 
M. MEYER, I. MIDDLEMIST, A. MIZSER, R. MODIC, M. MOELLER, J. MOLNAR, 
J. NEUMANN, J. NORDBY, S. O'CONNOR, E. OFEK, J. O'NEILL, J. OSORIO, S. PAPP, 
M. PERALA, J. PIETZ, G. POYNER, F. PUJOL, P. REINHARD, P. ROBBINS, 
M. RODRIGUEZ MARCO, R. ROYER, F. ROZSA, A. SAJTZ, C. SAPI, P. SCHMEER, 
C. SCOVIL, S. SHARPE, O. SHEMMER, N. SIMMONS, J. SPEIL, P. STEFFEY, R. STEWART, 
S. SWIERCZYNSKI, R. SZABO, L. SZENTASKO, P. TENGG, B. THOUET, J. VANDERLOOY, 
J. VANDIJK, F. VAN LOO, T. VANMUNSTER, P. VEDRENNE, J. VIALLE, W. VOLLMANN, 
D. WEIER, R. WEND, T. WESELAK, M. WESTLUND, D. WILLIAMS, J. WILMS, D. WILSON,
D. YORK, G. ZAJACZ.
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