OAA computing section circular NK 512 Periodic Comet Swift-Gehrels 1972 VII = 1981 XIX
The following improved orbital elements, by S. Nakano, are from 47 observations 1973 to 1982. Perturbations by all nine planets were taken into account. The mean residual is +/- 1.19 arc seconds: Epoch = 1981 Nov. 12.0 ET T = 1981 Nov. 27.45399 +/- 0.00028 (m.e.) ET Peri. = 84.53512 +/- 0.00076 Node = 314.03144 +/- 0.00074 (1950.0) Inc. = 9.24403 +/- 0.00012 q = 1.3610244 +/- 0.0000022 AU e = 0.6913271 +/- 0.0000005 a = 4.4092769 +/- 0.0000009 AU n_ = 0.10645180 +/- 0.00000003 P = 9.259 +/- 0.0000027 years T = 1972 Aug. 31.04679 ET Epoch = 1972 Aug. 31.0 ET Peri. = 84.40652 e = 0.6921035 Node = 314.23130 (1950.0) a = 4.3983018 AU Inc. = 9.25512 n_= 0.10685049 q = 1.3542217 AU P = 9.224 years The predicted orbit for the 1991 return is as follows: T = 1991 Feb. 22.67740 ET Epoch = 1991 Mar. 5.0 ET Peri. = 84.84777 e = 0.6916097 Node = 313.71777 (1950.0) a = 4.3941574 AU Inc. = 9.24995 n_= 0.10700170 q = 1.3551155 AU P = 9.211 years The following residuals in seconds of arc are from the above orbital elements: Date/ UT R.A. (1950) Decl. *** O-C *** Code/Obs h m s ! , " " " 1973 02 08.29308 08 07 28.31 +22 04 23.2 0.3+ 1.3- 675/PL 1973 02 09.29759 08 06 38.93 +22 01 19.8 1.0- 0.0 675/PL 1973 02 10.18046 08 05 57.25 +21 58 36.9 1.4- 2.2+ 801/HO 1973 02 10.23049 08 05 55.04 +21 58 26.6 1.4+ 1.4+ 801/HO 1973 02 25.06012 07 58 15.23 +21 09 38.1 1.3+ 0.4- 801/HO 1973 02 25.10506 07 58 14.28 +21 09 31.8 0.8- 2.5+ 801/HO 1973 02 28.19132 07 57 34.21 +20 58 48.0 ( 1.3+ 4.4-) 801/HO 1973 03 01.13459 07 57 25.73 +20 55 37.2 1.7+ 0.6+ 801/HO 1973 03 26.18993 08 02 42.04 +19 24 55.8 0.0 0.7- 691/ST 1973 03 26.23895 08 02 43.50 +19 24 44.6 0.5+ 0.6- 691/ST - continued - P/Swift-Gehrels NK 512 - 2 Date/ UT R.A. (1950) Decl. *** O-C *** Code/Obs. h m s ! , " " " 1981 07 11.28627 22 40 08.05 -07 38 49.3 ( 2.2- 5.4+) 801/HO 1981 07 31.26675 22 43 50.46 -04 41 57.5 1.1+ 1.7+ 801/HO 1981 08 01.23275 22 43 44.48 -04 33 17.4 0.2+ 0.0 801/HO 1981 08 02.28005 22 43 35.89 -04 23 51.7 0.5- 0.9- 801/HO 1981 08 05.70052 22 42 54.62 -03 52 47.0 ( 0.7- 5.3+) 372/sk 1981 08 24.94757 22 32 35.88 -00 55 21.1 0.3+ 1.7+ 046/KL 1981 08 24.96169 22 32 35.12 -00 55 13.2 0.3- 1.7+ 046/KL 1981 08 26.19737 22 31 35.06 -00 43 42.8 1.0+ 0.3- 801/HO 1981 08 28.93497 22 29 15.13 -00 18 13.8 0.9+ 2.8- 046/KL 1981 08 28.94914 22 29 14.31 -00 18 04.6 0.5+ 1.5- 046/KL 1981 09 01.54107 22 25 59.61 +00 15 27.3 ( 5.2+ 1.5-) 381/ks 1981 09 06.90943 22 20 52.41 +01 05 27.1 0.5+ 1.9+ 046/KL 1981 09 06.92378 22 20 51.39 +01 05 32.5 1.6- 0.7- 046/KL 1981 09 21.79773 22 07 28.32 +03 22 46.2 1.4- 0.4- 046/KL 1981 09 25.20950 22 05 03.25 +03 53 57.4 1.4- 1.2+ 801/HO 1981 09 29.99500 22 02 24.74 +04 37 36.8 1.2- 1.9+ 491/CN 1981 09 30.86552 22 02 03.01 +04 45 31.2 1.8+ 1.2- 491/CN 1981 10 28.83547 22 11 56.17 +09 19 58.1 1.3- 0.5- 491/CN 1981 10 29.75062 22 13 02.52 +09 30 00.7 0.4+ 3.2+ 020/NI 1981 10 29.94390 22 13 16.01 +09 32 04.5 1.3- 0.5- 491/CN 1981 11 02.95466 22 18 43.71 +10 16 59.3 0.6- 0.6- 801/HO 1981 11 05.22014 22 22 12.27 +10 43 08.5 1.0- 0.1+ 707/ev 1981 11 15.07535 22 40 39.95 +12 43 00.5 0.9+ 0.7- 707/ev 1981 11 15.7413 22 42 11.09 +12 51 55.3 (78.5+ 30.3+) 504/LL 1981 11 15.7525 22 42 12.30 +12 52 05.4 (75.6+ 31.8+) 504/LL 1981 11 23.00532 22 59 04.22 +14 25 24.3 0.1+ 2.3+ 801/HO 1981 11 25.83069 23 06 19.95 +15 02 44.7 2.5+ 1.0+ 491/CN 1981 11 26.74236 23 08 44.97 +15 14 49.8 0.3- 0.7- 552/SV 1981 11 26.74583 23 08 45.68 +15 14 50.3 2.1+ 2.9- 552/SV 1981 11 26.77500 23 08 50.09 +15 15 16.3 0.0 0.2- 552/SV 1981 11 26.83593 23 08 59.76 +15 16 05.9 0.1- 0.0 491/CN 1981 11 27.82813 23 11 40.17 +15 29 17.9 1.0- 0.5+ 489/HF 1981 11 27.83854 23 11 41.80 +15 29 26.2 1.4- 0.5+ 489/HF 1981 11 28.7729 23 14 15.48 +15 41 54.3 0.0 0.6- 494/mn 1981 11 28.7899 23 14 18.21 +15 42 06.9 0.3- 1.7- 494/mn 1981 12 01.75435 23 22 39.02 +16 21 56.1 ( 5.2+ 2.9+) 020/NI 1981 12 17.92882 00 13 14.56 +19 54 09.4 0.8+ 0.5+ 489/HF 1981 12 17.93576 00 13 15.90 +19 54 14.3 0.3+ 0.2+ 489/HF 1981 12 19.94704 00 20 01.63 +20 19 12.2 ( 6.5- 0.1+) 801/HO 1981 12 22.7538 00 29 36.14 +20 53 06.1 ( 5.0+ 0.7+) 494/mn 1981 12 22.76562 00 29 38.49 +20 53 17.6 ( 4.6+ 3.7+) 489/HF 1981 12 22.77326 00 29 39.72 +20 53 19.1 0.1+ 0.2- 489/HF 1981 12 22.7785 00 29 40.87 +20 53 21.5 1.1+ 1.6- 494/mn 1981 12 31.86875 01 01 23.82 +22 35 05.9 0.3- 1.0- 489/HF 1982 01 20.05162 02 09 17.42 +25 19 19.2 0.9- 0.1- 801/HO 1982 01 25.82203 02 29 18.69 +25 54 04.3 0.8- 0.5- 491/CN 1982 01 26.82069 02 32 44.60 +25 59 27.1 1.1+ 1.5+ 491/CN ( ) -------- Rejected Obs.
Director, Computing Section Syuichi Nakano 1987 August 20