OAA computing section circular NK 482 Periodic Comet Schwassmann-Wachmann 2 1961 VII = 1968 II
= 1974 XIII = 1981 VI The following improved orbital elements, by S. Nakano, are from 113 observations 1960 to 1982, including full planetary per- turbations and non-gravitational effect of style II. The mean residual is +/- 1.41 arc seconds. Epoch = 1981 Mar. 17.0 ET T = 1981 Mar. 17.03658 +/- 0.00069 (m.e.) ET Peri. = 357.45974 +/- 0.00103 Node = 125.94142 +/- 0.00102 (1950.0) Inc. = 3.72983 +/- 0.00010 q = 2.1350062 +/- 0.0000013 AU e = 0.3867061 +/- 0.0000004 a = 3.4812120 +/- 0.0000004 AU nß = 0.15174290 +/- 0.0000000004 P = 6.495 +/- 0.0000011 years A1 = +2.296 +/- 0.050 A2 = -0.17802 +/- 0.00104 T = 1961 Sept. 5.06498 ET Epoch = 1961 Sept.18.0 ET Peri. = 357.69743 e = 0.3828606 Node = 126.00195 (1950.0) a = 3.4955355 AU Inc. = 3.72342 nß= 0.15081116 q = 2.1572328 AU P = 6.535 years T = 1968 Mar. 14.28038 ET Epoch = 1968 Mar. 5.0 ET Peri. = 357.66260 e = 0.3844083 Node = 125.99563 (1950.0) a = 3.4883680 AU Inc. = 3.72655 nß= 0.15127621 q = 2.1474103 AU P = 6.515 years T = 1974 Sept.12.34425 ET Epoch = 1974 Sept.30.0 ET Peri. = 357.31170 e = 0.3855298 Node = 125.96993 (1950.0) a = 3.4861956 AU Inc. = 3.72713 nß= 0.15141763 q = 2.1421634 AU P = 6.509 years The predicted orbit for the 1987 return is as follows: T = 1987 Aug. 30.48447 ET Epoch = 1987 Sept. 2.0 ET Peri. = 357.88591 e = 0.3984222 Node = 125.66018 (1950.0) a = 3.4433324 AU Inc. = 3.75579 nß= 0.15425372 q = 2.0714325 AU P = 6.390 years There are the residuals, in seconds of arc, from the above orbital elements on the next page: - continued - NK 482 - 2 Date/ UT R.A. (1950) Decl. *** O-C *** Code/Obs. h m s ¡ , " " " 1956 05 16.41460 15 38 38.64 -14 23 51.0 ( 8.8- 2.6+) 662/LI 1956 05 16.45929 15 38 36.51 -14 23 43.8 ( 8.1- 3.3+) 662/LI 1956 05 29.21972 15 28 49.31 -13 56 24.0 ( 9.5- 2.0+) 662/LI 1956 05 29.26549 15 28 47.42 -13 56 19.1 ( 7.5- 1.9+) 662/LI 1960 08 18.32124 02 31 25.02 +10 31 15.9 0.3- 0.0 689/FS 1960 08 18.37249 02 31 26.28 +10 31 17.2 0.1- 0.5- 689/FS 1960 09 25.36523 02 33 28.51 +09 42 01.2 1.1+ 0.5- 689/FS 1960 09 25.41023 02 33 27.49 +09 41 52.6 0.5+ 0.7- 689/FS 1960 10 14.24698 02 23 37.75 +08 30 07.8 0.0 0.3- 689/FS 1960 10 14.28299 02 23 36.27 +08 29 58.4 0.6+ 0.4- 689/FS 1960 11 09.22993 02 03 29.91 +06 38 31.4 0.7+ 1.0- 689/FS 1960 12 18.16907 01 45 55.44 +05 50 43.3 1.8+ 0.3+ 689/FS 1960 12 18.23348 01 45 55.28 +05 50 49.6 1.8+ 0.3+ 689/FS 1961 01 07.16038 01 50 24.10 +06 51 36.2 1.1+ 0.5- 689/FS 1961 01 07.18601 01 50 24.76 +06 51 43.2 0.8+ 0.1- 689/FS 1961 02 06.10183 02 13 22.60 +09 44 29.9 3.2+ 0.6+ 689/FS 1961 02 06.12745 02 13 24.15 +09 44 40.2 2.7+ 0.4+ 689/FS 1961 03 15.12218 03 02 10.99 +14 22 24.3 2.7+ 2.6+ 689/FS 1961 03 15.15352 03 02 13.92 +14 22 38.3 2.8+ 2.2+ 689/FS 1961 10 18.47592 10 42 06.72 +08 58 02.9 ( 6.1+ 0.8-) 689/FS 1961 11 18.47560 11 38 18.70 +03 49 55.1 3.8+ 0.1+ 689/FS 1961 11 18.48532 11 38 19.74 +03 49 49.8 ( 4.8+ 0.2+) 689/FS 1961 12 04.48492 12 03 57.12 +01 29 52.7 ( 5.3+ 0.6+) 689/FS 1961 12 04.49603 12 03 58.07 +01 29 46.9 ( 4.6+ 0.2+) 689/FS 1962 01 15.41494 12 54 26.34 -02 29 44.4 0.8+ 1.0+ 689/FS 1962 01 15.44619 12 54 27.85 -02 29 49.7 1.0+ 1.0+ 689/FS 1962 01 30.40612 13 04 05.87 -02 53 40.7 0.4- 1.2+ 689/FS 1962 01 30.42001 13 04 06.24 -02 53 41.0 0.3- 1.2+ 689/FS 1962 03 01.06250 13 05 38.35 -01 49 49.1 1.4- 2.2+ 056/SP 1962 03 01.10417 13 05 37.40 -01 49 38.4 1.7- 1.9+ 056/SP 1962 03 03.31551 13 04 48.05 -01 39 37.1 0.2- 0.9+ 689/FS 1962 03 03.34954 13 04 47.21 -01 39 27.8 0.4+ 0.7+ 689/FS 1962 04 03.35193 12 44 47.19 +01 08 14.7 0.4- 1.3+ 689/FS 1962 04 24.28939 12 31 29.11 +02 27 18.3 0.9- 1.6+ 689/FS 1962 04 24.31300 12 31 28.41 +02 27 21.5 0.7- 1.6+ 689/FS 1962 05 22.19182 12 26 22.80 +02 25 34.6 1.3- 1.8+ 689/FS 1962 05 22.21196 12 26 22.87 +02 25 31.5 2.0- 1.4+ 689/FS 1967 09 08.45694 05 38 52.57 +19 57 43.7 ( 8.2- 2.4-) 693/CT 1968 01 02.95789 06 21 52.01 +20 11 39.0 ( 0.6+ 3.9+) 020/ml 1968 01 02.96968 06 21 51.28 +20 11 39.6 1.2- 2.7+ 020/NI 1968 01 06.08744 06 19 22.65 +20 20 04.5 0.7- 2.0+ 020/NI 1968 01 06.10330 06 19 21.97 +20 20 09.0 ( 0.5+ 4.1+) 020/NI 1968 01 18.76266 06 10 45.67 +20 55 54.7 0.9- 0.1+ 020/NI 1968 01 18.77652 06 10 45.30 +20 55 57.2 0.5+ 0.1+ 020/NI 1968 01 23.77576 06 08 20.78 +21 10 17.6 1.5- 1.8- 020/NI 1968 01 23.79723 06 08 20.40 +21 10 25.2 1.1+ 1.9+ 020/NI 1968 01 25.76013 06 07 35.74 +21 15 58.0 2.1+ 2.5- 020/NI 1968 01 25.78160 06 07 35.38 +21 16 06.4 3.8+ 2.1+ 020/ml 1968 01 25.98125 06 07 30.42 +21 16 39.4 1.1- 1.5+ 056/SP 1968 01 26.02292 06 07 29.52 +21 16 45.3 1.0- 0.6+ 056/SP - continued - NK 482 - 3 Date/ UT R.A. (1950) Decl. *** O-C *** Code/Obs. h m s ¡ , " " " 1968 01 30.18785 06 06 21.13 +21 28 38.7 1.5- 0.9+ 693/CT 1968 02 01.79965 06 05 55.88 +21 35 57.6 0.2+ 1.0+ 095/CR 1968 02 17.48279 06 08 25.34 +22 17 27.8 ( 0.9+ 10.3+) 370/sk 1968 02 19.55913 06 09 23.16 +22 22 13.6 0.5- 1.4- 370/sk 1968 02 21.56028 06 10 27.83 +22 26 52.5 ( 6.8+ 0.7-) 370/sk 1968 02 21.75295 06 10 33.96 +22 27 18.7 2.2- 0.0 095/CR 1968 02 21.75300 06 10 34.10 +22 27 19.2 0.2- 0.5+ 095/CR 1968 02 27.82483 06 14 38.89 +22 40 18.6 1.6+ 0.6- 020/NI 1968 03 31.16523 06 53 08.75 +23 10 24.1 0.8+ 0.1- 693/CT 1968 05 26.17644 08 35 43.52 +20 01 14.0 0.3- 0.2+ 693/CT 1968 05 26.18477 08 35 44.50 +20 01 10.9 0.4- 0.3+ 693/CT 1969 03 15.38897 15 55 38.81 -15 49 45.8 ( 7.3- 3.3+) 693/CT 1969 03 15.45148 15 55 39.13 -15 49 42.7 ( 7.3- 3.2+) 693/CT 1969 04 20.39794 15 45 09.45 -14 41 20.6 ( 9.3- 3.1+) 693/CT 1969 04 20.44447 15 45 07.59 -14 41 13.4 ( 9.4- 2.8+) 693/CT 1969 04 21.35000 15 44 32.43 -14 38 49.2 (10.9- 1.1+) 693/CT 1969 05 18.24513 15 24 02.95 -13 25 31.5 (10.6- 3.4+) 693/CT 1969 05 18.29166 15 24 00.68 -13 25 24.6 (10.9- 3.5+) 693/CT 1973 08 28.08056 02 24 21.48 +09 40 51.9 0.2- 0.8+ 056/SP 1973 08 28.10556 02 24 21.63 +09 40 51.5 1.7- 1.4+ 056/SP 1973 08 29.31319 02 24 34.18 +09 39 59.5 1.1- 1.4+ 801/HO 1973 09 04.39236 02 25 11.18 +09 33 20.7 0.1+ 0.2+ 693/CT 1973 09 04.43611 02 25 11.24 +09 33 17.6 0.2+ 0.7+ 693/CT 1973 09 21.34016 02 22 55.30 +08 55 11.4 1.5+ 1.1+ 691/ST 1973 09 21.37112 02 22 54.69 +08 55 05.8 1.7+ 1.2+ 691/ST 1973 09 26.20755 02 21 09.54 +08 39 07.4 1.2- 1.9+ 801/HO 1973 09 27.72708 02 20 30.5 +08 33 38 1.8- 1.8- 380/kj Y 1973 09 27.75139 02 20 29.8 +08 33 36 2.1- 1.6+ 380/kj Y 1973 09 28.95961 02 19 56.98 +08 29 06.9 3.3- 0.8+ 046/KL 1973 09 28.98096 02 19 56.43 +08 29 03.8 2.3- 2.5+ 046/KL 1973 10 06.19063 02 16 06.34 +08 00 13.9 0.7- 1.1+ 801/HO 1973 10 21.32263 02 05 33.00 +06 51 49.4 0.9+ 0.5+ 691/ST 1973 10 21.32992 02 05 32.65 +06 51 47.3 1.0+ 0.5+ 691/ST 1973 10 22.67708 02 04 29.2 +06 45 39 ( 3.6- 8.3+) 380/kj Y 1973 10 24.20569 02 03 17.20 +06 38 24.6 0.6- 0.7- 774/WN 1973 10 24.22583 02 03 16.23 +06 38 20.4 0.4- 0.6+ 774/WN 1973 10 25.64444 02 02 08.37 +06 31 48.2 3.1- 0.4- 372/sk 1973 10 25.66389 02 02 07.40 +06 31 43.6 3.3- 0.4+ 372/sk 1973 11 24.53626 01 40 50.06 +04 48 29.6 1.2+ 0.6+ 879/fr 1973 11 24.55174 01 40 49.42 +04 48 27.2 0.8- 0.2- 879/fr 1975 01 12.59865 12 44 24.50 -01 37 29.9 2.2- 0.9+ 485/CA 1975 01 13.25380 12 44 58.51 -01 39 32.9 0.9+ 0.4- 805/EL 1975 01 14.25860 12 45 49.04 -01 42 30.7 0.9- 0.5- 805/EL 1975 01 17.75069 12 48 34.07 -01 51 36.8 2.9- 1.1- 372/sk 1975 01 23.77986 12 52 38.32 -02 02 20.1 1.6- 0.8- 372/sk 1975 03 18.52513 12 46 47.72 +00 40 02.6 2.7- 0.5+ 485/CA 1975 03 21.73681 12 44 30.77 +00 58 31.5 1.4+ 3.0- 372/sk 1975 04 11.31181 12 29 38.39 +02 43 32.8 1.0+ 2.5- 774/WN 1975 04 12.55396 12 28 50.70 +02 48 29.3 2.1+ 2.2+ 330/TS 1975 04 15.18414 12 27 12.89 +02 58 01.7 0.1+ 1.6- 805/EL - continued - NK 482 - 4 Date/ UT R.A. (1950) Decl. *** O-C *** Code/Obs. h m s ¡ , " " " 1975 04 18.10537 12 25 32.56 +03 07 13.2 1.2+ 0.9- 801/HO 1975 04 18.12493 12 25 31.76 +03 07 24.6 0.7- 0.7+ 805/EL 1975 04 18.40000 12 25 22.84 +03 08 10.9 0.3- 1.8- 485/CA 1975 04 29.14348 12 20 39.34 +03 29 31.1 2.2+ 0.3+ 801/HO 1975 05 08.07838 12 18 34.28 +03 32 31.5 0.2- 1.1- 805/EL 1975 05 09.26597 12 18 25.66 +03 31 51.5 2.0+ 0.6+ 693/CT 1975 05 09.31597 12 18 25.27 +03 31 49.8 2.0+ 0.8+ 693/CT 1975 06 04.22668 12 22 46.30 +02 27 06.8 3.6+ 0.9+ 691/ST 1975 06 04.24983 12 22 46.88 +02 27 00.7 3.9+ 0.5+ 691/ST 1975 06 11.09775 12 26 03.28 +01 56 13.9 0.0 0.5+ 801/HO 1979 12 14.98141 23 39 07.87 -06 03 01.2 2.8- 3.0- 801/HO 1979 12 15.99677 23 39 34.00 -05 59 25.7 1.4+ 0.3+ 801/HO 1980 11 09.36183 06 34 18.65 +19 09 17.8 1.0- 0.2- 801/HO 1980 12 05.36524 06 31 39.50 +19 14 48.8 1.3- 0.0 801/HO 1980 12 05.55068 06 31 34.37 +19 15 09.9 1.5- 0.2+ 474/JN 1980 12 05.57344 06 31 33.71 +19 15 11.4 0.7- 0.2+ 474/JN 1980 12 11.31442 06 28 20.3 +19 22 28 ( 8.9- 1.5+) 711/MC Y 1980 12 29.46398 06 14 37.62 +19 58 21.3 0.0 1.1- 386/te 1980 12 29.47998 06 14 36.82 +19 58 24.8 0.2+ 0.0 386/te 1980 12 29.49144 06 14 36.23 +19 58 26.3 0.1+ 0.3- 386/te 1980 12 31.49722 06 12 58.44 +20 03 18.1 0.9+ 1.1- 386/te 1980 12 31.50856 06 12 57.84 +20 03 19.2 0.5+ 1.8- 386/te 1981 01 03.73854 06 10 22.47 +20 11 22.4 ( 1.8- 4.8-) 386/te 1981 01 05.67778 06 08 52.56 +20 16 26.2 1.3- 1.8- 386/te 1981 01 08.51777 06 06 46.67 +20 23 57.2 1.1+ 0.2- 386/te 1981 01 08.52951 06 06 46.12 +20 23 59.7 0.9+ 0.4+ 386/te 1981 01 09.54057 06 06 02.98 +20 26 41.2 1.0+ 0.5- 386/te 1981 01 09.55174 06 06 02.44 +20 26 41.2 0.4+ 2.3- 386/te 1981 01 11.15648 06 04 56.35 +20 31 02.4 0.9+ 0.2- 801/HO 1981 01 26.27432 05 57 43.48 +21 13 14.3 1.0- 0.3- 675/PL 1981 02 28.05851 06 07 59.93 +22 38 27.0 0.1- 0.8- 801/HO 1982 05 15.29305 15 25 56.17 -13 30 36.8 2.4+ 0.0 675/PL 1982 05 16.33819 15 25 05.91 -13 27 56.4 1.4- 0.9- 675/PL 1982 05 16.37292 15 25 04.18 -13 27 49.8 1.8- 0.3+ 675/PL 1982 05 17.30764 15 24 20.01 -13 25 29.2 1.4+ 1.1- 675/PL 1982 05 18.36597 15 23 29.82 -13 22 48.9 1.3+ 0.7+ 675/PL ( ) -------- Rejected Obs.
Director, Computing Section Syuichi Nakano 1985 December 16