COMMISSION 27 OF THE I. A. U.
            INFORMATION BULLETIN ON VARIABLE STARS
                          NUMBER 76


                                         Konkoly Observatory
                                         Budapest
                                         23 December 1984


                    LIGHT VARIATIONS OF THE
                MAGNETIC-VARIABLE STAR HD 10783


     HD 10783 (= BD +7deg275), spectrum A2p, is one of this magnetic 
variable stars mentioned in the catalogue of Babcock (Ap. J. Supp.
no 3, 1957). Steinitz (1964, Leiden thesis) derived far the magnetic
variations a period of 4d.134. The dispersion in the magnetic measures
is however still rather large. During 23 nights in 1964 this star has
been observed photoelectrically at the Leiden Observatory with the
45-cm Zunderman reflector. A red filter (effective wavelength 5960 A)
has been used. The comparison star was BD +8deg258 (= HD 10262), of
spectral type F2. The normal points in the figure are means of about
ten individual observations, corrected for differential extinction. The
values of the differential extinction between variable and comparison
seldom exceeded 0m.007.


                          [FIGURE 1]

      From our measures we derived a better and more accurate
period of 4d.1565 for the photoelectric as well as for the magnetic 
variations. The phases have been computed with the formula:

           phase = (JD - 243 0000) X.240587.

     The observations will be published in the B. A. N.


                          A. M. VAN GENDEREN
                          Leiden Observatory