Circular No. 3496 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. TWX 710-320-6842 ASTROGRAM CAM Telephone 617-864-5758 SATELLITES OF SATURN The Space Telescope Wide Field/Planetary Camera Instrument Definition Team reports the following observations of new satellites of Saturn, made at the U.S. Naval Observatory in Flagstaff with the 1.5-m astrometric reflector, using a 500 x 500-pixel CCD system developed by the ST/WFC Team for ground-based use. This is a preliminary and incomplete list of measures of the positions of the images. The accuracy of the separations east (+) or west (-) of the center of Saturn (in the plane of the rings) is ~ 0".5. 1980 S 1 (= 1966 S 2?), mR ~ 14. Mar. 13.17853 UT, -24".0; 13.18492, -24".3; 13.22638, -20".5 (on rings); 13.25174, -16".9 (on rings); 14.21100, +24".5. 1980 S 3, mR ~ 15. Mar. 9.30567 UT, -24".9; 9.30897, -24".9; 9.30975, -25".1. 1980 S 6, mR ~ 18. Mar. 9.39498 UT, +57".9; 9.40216, +57".6; 9.42662, +56".9; 10.31414, -47".0; 10.31968, -47".5; 10.32358, -47".7; 10.34718, -49".8; 13.18171, -56".6; 13.18788, -56".9; 13.26449, -60".0. 1980 S 25 (probably distinct from 1980 S 6), mR ~ 18. Mar. 13.36949, -44".1; 13.38126, -44".6. H. J. Reitsema, Lunar and Planetary Laboratory, informs us that A. W. Harris and himself consider that 1980 S 9 = 1980 S 1 (= 1966 S 2?). He adds that observations around Mar. 14 show a very definite brightness enhancement at 2.20 +/- 0.02 radii on each side of Saturn due to the transparency of the Encke Division. It is possible that 1980 S 7 and 1980 S 23 represent observations of this phenomenon, rather than discrete Saturnian satellites. AM HERCULIS G. D. Schmidt, Lick Observatory; H. S. Stockman, Steward Observatory; and B. Margon, University of Callfbrnla at Los Angeles, write: "We have obtained spectropolarimetric and spectrophotometric observations of AM Her (cf. IAUC 3490) with the ITS on the 3-m Shane reflector at the Lick Observatory. The data, obtained over several orbital periods during July 18-20, show circularly polarized Zeeman-shifted photospheric absorption features of hydrogen in a magnetic field of strength 14-18 MG. Previous indirect estimates of the field strength have been in excess of 100 MG." 1980 July 31 (3496) Brian G. Marsden
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