COMMISSION 27 OF THE I.A.U.
              INFORMATION BULLETIN ON VARIABLE STARS
                           Number 1266

                                                    Konkoly Observatory
                                                    Budapest
                                                    1977 April 18

               FLARE ACTIVITY ON G12-30

We have observed two prominent flares on the star G12-30
(RA= 12h16m31s Dec.= 11d24.0',1950) during seven nights of monitoring 
it as part of a survey of nearby late M dwarfs. Photometric
observations were made in the B-band of the UBV system using
the 60-inch (1.5 m) telescope of the Hale Observatories at Mt.
Wilson. Time resolution was limited to ten-second integrations.
The sky background was measured at three minute intervals. After
subtracting the sky background, the signal was ratioed to the
quiescent state of the object. A total time of 14.6 hours was
spent integrating on the object itself during the periods 
February 9-11 and February 26 - March 1, 1977 (UT).
Harrington et al. (1975) list the following data for G12-30:

                   m_v = 13.79
                   B-V =  1.83
                    pi = 0.151"

which implies that the object is a late M dwarf. Image tube
spectra previously obtained by Veeder (unpublished) indicate a
late M type with strong H-alpha in emission. Thus, G12-30 is
probably a UV Ceti type flare star.
   This paper presents the results of one phase of research
carried out at the Jet Propulsion Laboratory, California Institute 
of Technology, under contract NAS 7-100, sponsored by the
National Aeronautics and Space Administration.


                    [FIGURE 1]
                    [FIGURE 2]


                                GLENN J. VEEDER *
                                OLAV L. HANSEN **

* Guest Investigator,Hale Observatories California Institute of
  Technology and Carnegie Institution of Washington
** National Research Council, Resident Research Associate



References:

Harrington, R.S., Dahn, C.C., Behall, A.L., Priser, J.B., Christy, J.W.,
   Riepe, B.Y., Ables, H.D., Guetter, H.H., Hewitt, A.V. and Walker, R.L.
   (1975), Publ. U.S. Naval Observatory, Vol. XXIV, Part 1 [BIBCODE 1975PUSNO..24a...1H ]