COMMISSION 27 OF THE I. A. U.
       INFORMATION BULLETIN ON VARIABLE STARS
                    NUMBER 376

                                 Konkoly Observatory
                                 Budapest
                                 1969 September 10


          THE LIGHT CURVE OF 442 CAS (S 9484)
    DURING THE ECLIPSE OBTAINED BY T.V. OBSERVATIONS

      The variable 442 Cas (S 9484) of the Algol-type was
discovered by Hoffmeister in 1966. Its magnitudes at maximum
and minimum and its element were found to be 12.5m, 17.0m 
and 
	T_min = 2430262.430d + 3.59225d E
             
respectively (1). The minimum of the light curve is narrow
and covers 0.09 of the period. To measure the minimum
brightness by the method of photography is difficult owing
to long exposures.

                         [FIGURE 1]

Fig. 1: Light curve of 442 Cas during the eclipse. The different
marks corresponds to different nights:
full square - J. D. 2440213, x - 38, empty triangle: 41, 
empty circle - 45, full circle - 63, full triangle - 74.


      The television observations of 442 Cas were made
with the 0.5-meter telescope at the Crimean Astrophysical
Observatory in the winter of 1968-1969. A new pick-up tube
of high sensitivity with a multialkaly photocathod and
yellow filter was used (2). The effective wavelength for
stars of the spectral type G2 is 5500 A. The colour system
is near that of the V. The exposure time of T. V. photographs
was 1-4 minutes: 290 photographs of the variable in the
phases 0.9-0.0-0.1 were taken during 8 nights. About 100
photographs in the minimum brightness were taken. The open
cluster NGC 188 and NGC 7789 were observed as standards.
The magnitudes of 32 stars in the neighbourhood of the
variable were determined. The mean square error of a single
observation is 0.1m. The maximum and minimum brightnesses of
442 Cas are 12.53m and 15.73m respectively. The light curve
of the variable during the eclipse, drown from the elements
mentioned above, is shown in the figure. Each mark is a
normal point consisting of 3-6 observations. The variations
of the minimum brightness are possibly real. It is interesting
to note the peaks in the light curve before and after the
minimum.
      The epoch of the minimum observed is

           T_min = 2440245.289d +/-   0.002d

Crimean Astrophysical Observatory, USSR
26. 8. 1969



                   V. V. PROKOFJEVA, V. P. EPISHEV





REFERENCES

(1) Inf. Bull. on Var. St., Com. 27 of the I. A. U. 1968, N 269 [IBVS 269]
(2) A. N. Abramenko, P. P. Petrov, V. V. Prokofjeva, Astr. Circ.
    USSR, 1968; N 491. [BIBCODE 1968ATsir.491....1A ]