COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                     NUMBER 292

                                 Konkoly Observatory
                                 Budapest
                                 1968 August 13


               NOTE ON V 381 SCORPII


The latest minimum of the long period eclipsing binary V 381 Scorpii occurred
in 1961/62. The photometric elements derived by Henrietta Swope (1936) are:

Min=J.D. 2424574+6475 E; D=670^d, d=300^d.

In order to check the prediction for 1962, at the request of Dr.T. Herczeg, 13
exposures of the region were kindly secured by Dr.E. Geyer, using the 10-inch
Metcalf Telescope of the Boyden Observatory. The plates (103a-O) represent the
time interval May-June 1962 (J.D. 2437795- 2437845) and should correspond to
the end of the egress phase, the 4th contact being predicted for J.D. 2437859.

An inspection of the plates shows, however, that the earlier component must
have been still completely eclipsed at that time or, at most, just passed the
3rd contact. The variable appears slightly fainter than star No. 46 in M6
(Catalogue of Rohlfs et al., 1959), having B=15.8, i.e. V 381 Scorpii was very
nearly at its minimum level. In spite of the considerable scatter there is a
tendency of the variable growing brighter towards June, by perhaps 0.3 magn.
The 3rd contact may have taken place about J.D. 2437820.


                          [FIGURE 1]

This means that the ephemeris was sensibly in error, with O-C ~140^d. A
correspondingly improved value of the period amounts then to P=6545^d which
turns out, in fact, to be compatible with the earlier measurements, too. The
epoch of mid-eclipse, as given by Miss Swope, is rather well defined by the
best observed minimum of 1926.

A chart of the immediate vicinity of V381 Scorpii is also added here because of
the very crowded star field around. The brightest star at the left (eastern)
edge is CD -35d11934; the variable is indicated by an asterisk.


Hamburg, August 8, 1968.
                                      H. TIMMERMANN
                                   Hamburg Observatory

References:

H.H. Swope: Harvard Bull. 902, 6, 1936
K. Rohlfs, K.W. Schrick and J. Stock: Z. Astrophys. 47, 15, 1959.