COMMISSION 27 OF THE I.A.U. INFORMATION BULLETIN ON VARIABLE STARS NUMBER 111 Konkoly Observatory Budapest 27 October 1965 MINIMA OF ECLIPSING VARIABLES Given are 78 observed minima for 27 eclipsing variable stars. All are visual timings reduced by the tracing-paper method, except where noted. Elements in the 1958 General Catalogue of Variable Stars were used to compute O - C's unless otherwise specified. The number of estimates used for each minimum is given under n. J.D. hel. E O - C n Observer RT Andromedae 2438252.584 +22,472 -0.023 18 J. Ashbrook 38931.834 +23,552 -0.020 8 D. Williams KO Aquilae 38931.800 +1.761 -0.009 13 D. Williams OO Aquilae 38927.687 +9,276.5 -0.017 9 C. Ricker 38928.704 +9,278,5 -0,014 14 D. Williams 38931.745 +9,284.5 -0.013 9 D. Williams 38935.806 +9,292.5 -0.007 11 M. Murphy 38936.813 +9,294.5 -0.013 11 R. Monske 38937.824 +9,296.5 -0.016 12 R. Monske 38938.840 +9,298.5 -0.014 12 R. Monske 38964.674 +9,349.5 -0.026 8 D. Williams 38966.715 +9,353.5 -0.012 8 D. Williams V342 Aquilae 1/ 38955.750 +980 +0.009 33 R. Monske 38972.707 +985 +0.011 33 R. Monske V346 Aquilae 38967.712 +6,904 -0.018 10 D. Williams WW Aurigae 24 38755.618 +2,175 -0.011 20 D. Friedman 38770.759 +2,181 -0.001 20 M. Baldwin 38808.630 +2,196 -0.003 11 M. Baldwin 38813.679 +2,198 +0.004 17 M. Baldwin 38813.567 +2,213 +0.009 8 T. Hering SV Camelopardalis 38892.665 +11,137 -0.022 16 M. Murphy 38927.673 +11,196 -0.005 17 M. Murphy R Canis Maioris 38817.533 +2,907 +0.001 16 H. Marraco 38818.6683 2/ +2,908 +0.0006 27pe J. Ruiz, D. Taboada RZ Cassiopeiae 38770.721 +17,917 -0.031 17 M. Baldwin 38782.669 +17,927 -0.035 18 M. Baldwin 38788.645 +17,932 -0.035 16 M. Baldwin 38794.625 +17,937 -0.032 13 M. Baldwin 38966.740 +18,081 -0.033 8 D. Williams U Cephei 38727.708 +12,370 +0.729 44 M. Baldwin XX Cephei 38727.708 +5,832 -0.076 15 M. Baldwin U Coronae Borealis 38938.738 +6,428 +0.006 35 D. Friedman 38938.742 +6,428 +0.010 17 R. Monske Z Draconis 38881.727 +4,135 +0.015 20 D. Williams 38915.658 +4,160 +0.010 16 R. Monske 38938.739 +4,177 +0.015 11 R. Monske 38953.672 +4,188 +0.016 12 R. Monske AI Draconis 38902.765 +11,899 +0.012 9 D. Williams 38938.729 +11,929 +0.012 11 D. Williams 38938.744 +11.929 +0.027 34 D. Friedman Z Herculis 38931.752 +1,285 +0.007 16 D. Williams 38967.680 +1,294 0.000 13 D. Williams 38971.684 +1,295 +0.011 9 D. Williams SZ Herculis 38879.885 +2,143 +0.010 20 M. Baldwin 38888.883 +2,154 +0.009 13 M. Baldwin 38902.795 +2,171 +0.014 14 T. Cragg 38902.795 +2,171 +0.014 16 D. Williams 38916.702 +2,188 +0.013 11 R. Monske 38920.792 +2,193 +0.013 15 M. Murphy 38925.699 +2,199 +0.011 13 R. Monske 38938.782 +2,215 +0.004 16 G. Brown 38938.790 +2,215 +0.012 12 R. Monske 38943.702 +2,221 +0.016 11 R. Monske 38952.697 +2,232 +0.012 10 R. Monske 38956.787 +2,237 +0.011 16 R. Swanberg 38961.692 +2,243 +0.008 9 W. Hampton 38965.788 +2,248 +0.013 16 R. Swanberg 38988.701 +2,276 +0.020 15 R. Swanberg u Herculis 38937.745 +16,142 +0.037 10 D. Williams SW Lacertae 38967.740 +48,625.5 +0.024 10 D. Williams 38969.663 +48,631.5 +0.022 7 D. Williams SS Librae 38916.681 +12,980 +0.006 13 R. Monske 38952.638 +13,005 +0.013 13 R. Monske Delta Librae 38880.842 +1,901 +0.001 23 M. Baldwin 38920.4050 4/ +1,918 -0.0007 33pe L. Kalish 38943.670 +1,928 -0.009 18 R. Monske FL Lyrae 38173.640 +1,982 +0.004 17 J. Ashbrook U Ophiuchi 38919.725 +18,267 +0.005 8 T. Cragg 38966.684 +18,295 -0.002 13 D. Williams 38971.707 +18,298 -0.011 7 D. Williams RV Ophiuchi 38911.787 +4,045 -0.017 7 T. Cragg RT Persei 38770.603 +6,572 -0.012 8 M. Baldwin U Sagittae 38938.796 +6,451 +0.012 23 R. Monske 38955.696 +6,456 +0.009 21 R. Monske V505 Sagittarii 38938.760 +4,585 -0.035 12 R. Monske 38938.774 +4,585 -0.021 8 D. Williams BV 312 Tauri 5/ 38770.754 +6,385 +0.013 20 M. Baldwin 38805.696 +6,402 -0.002 22 M. Baldwin These results continue the lists published in "Sky and Telescope" (27, 58, 1964; 29, 254, 1965) from amateur observations. Expansion of this program has led to sponsorship by the American Association of Variable stars, with David B. Williams as coordinator. The reductions are made by the writer, in collaboration with Joseph Ashbrook, except in a few cases which were only checked. L. J. Robinson "Sky and telescope" 49 Bay State Rd. Cambridge, Mass. 02138 USA Notes to Table 1./ O - C's were computed from the elements given in IBVS, No. 92, Min = JDhel 2435632.603 + 3.3909547day E 2./ Reduced bye Kwee - van Woerden method. The probable error of the time of minimum is +/- 0.0014 day. 3./ O - C's were computed from the elements in Sky and telescope, 25, 5, 277. 4./ Time of minimum determined from 19 observations on JD 38908 and 14 observations on 38929. 5./ O - C's were computed from the elements given in Sky and telescope, 26, 5, 264.