COMMISSION 27 OF THE I. A. U.
                INFORMATION BULLETIN ON VARIABLE STARS
                           Number 2531

                                             Konkoly Observatory
                                             Budapest
                                             7 June 1984

                                             HU ISSN 0374-0676


                   COORDINATED SS CYGNI OBSERVATIONS

  Coordinated Voyager far-UV (500 - 1700 A) and IUE (1200 - 3200 A) observations
of the cataclysmic variable SS Cygni during two outbursts are planned
for this summer. Analysis of AAVSO data on SS Cygni obtained since 1980
suggests the following dates for the beginning of the outburst: July 1+-5, 1984
an  August 25 +-5, 1984. In visual light SS Cyg brightness increases from
V approx. 11.8 to V approx. 8.5 during the first 24 hours of an outburst then
declines back to V approx. 11.8 over the next 7 to 17 days. We encourage 
observations in other spectral regions during these outbursts.



R.S. POLIDAN and J.B. HOLBERG                       A.V. HOLM
Lunar and Planetary Laboratory                Computer Science Corporation
University of Arizona                         Systems Sciences Division
3625 E. Ajo Way                               Space Telescope Institute
Tucson, Arizona 85713                         Johns Hopkins University
(602) 621-4301                                Baltimore, Maryland 21218

  J.A. MATTEI
  American Association of
  Variable Star Observers
  187 Concord Avenue
  Cambridge, Massachusetts 02138