Circular No. 3483 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 J. Lecacheux, Observatoire de Meudon, reports the following analyses and further electronographic observations by P. Laques at Pic du Midi and by G. Wierick and G. Lelievre at Haute Provence of separations of satellites (+ = east, - = west) from Saturn's center: 1966 S 2 = 1980 S 1 = 1980 S 2: Mar. 1.0488 UT, +22".16; 17.031, +21".83. Revised elements from the data on IAUC 3470-3474: greatest eastern elongation = 1980 Mar. 18.317 UT + light time + 0.0019 (U - 45o.6) + 0.69465 E. The identities with 1979 S 7 and 1979 S 1 are invalid, the orbital longitude of 1966 S 2 at the time of the closest approach of Pioneer 11 having been L = 121o +/- 3o. [Editorial Note. It now seems probable that the correct definition of 1966 S 2 is orbit 16 in the paper by Aksnes and Franklin (1978, Icarus 36, 107); see also Fountain and Larson (1978, ibid. 36, 92). The designation 1966 S 1 refers to an orbit with period 0.75 day, and no object with this period is now believed to exist.] 1980 S 3 = 1980 S 4 = 1980 S 5 = 1980 S 8 (observation on IAUC 3463 only) = 1980 S 11 = 1980 S 15 = 1980 S 16 = 1980 S 17 = 1980 S 19: Mar. 17.009 UT, -21".6; 18.040, +22".3. Elements (fitting the indicated observations with a standard deviation of 0".5): greatest eastern elongation = 1980 Mar. 18.645 UT + light time + 0.0019 (U - 45o.6) + 0.6939 E. Other published observations (i.e., 1979 S 7, 1980 S 7, 1980 S 9, 1980 S 18, 1980 S 20, 1980 S 21 and the IAUC 3466 observation attributed to 1980 S 8 [here redesignated 1980 S 23: Ed.] do not fit any single circular solution. [Editorial Note. The suggestion that there exists a second satellite essentialy in the orbit of 1966 S 2 and about 180o from it was privately made to the Central Bureau by B. A. Smith, University of Arizona, early in March. It is quite possible that 1980 S 3 = 1979 S 1, for which W. H. Blume has given the time of greatest western elongation (at Saturn) as 1979 Aug. 31.997 +/- 0.004 UT. 1979 S 2 and 1979 S 4 can together presumably be related to 1966 S 2 and 1980 S 3.] 1980 S 6 = 1980 S 10 = 1980 S 12 = 1980 S 14: Mar. 1.030 UT, +62".4; 1.049, +62".2; 1.099, +61".4; 1.131, +59".9 (refinement to IAUC 3457). [Editorial Note. The suggestion that 1980 S 6 = 1980 S 10 with period 2.75 days was included with the information provided by P. Lamy and N. Mauron for publication on IAUC 3463. Both Smith and Lecacheux have suggested that 1980 S 6 is associated with the triangular libration point leading Saturn IV (Dione). It is possible that 1980 S 13 is associated with the corresponding trailing point.] 1980 June 6 (3483) Brian G. Marsden
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