OAA computing section circular NK 1316 64P/Swift-Gehrels
The following improved orbital elements, by S. Nakano, are from 62 observations 1973 to 2001, including planetary perturbations by Mercury to Neptune and three minor planets, Ceres, Pallas, Vesta, and non-gravitational effect of style II. The mean residual is +/- 0.92 arc second. See previous orbits in NK 652 and on MPC 41899. Epoch = 2000 Apr. 6.0 TT T = 2000 Apr. 21.80389 +/- 0.00057 (m.e.) TT Peri. = 92.41371 +/- 0.00022 Node = 306.14076 +/- 0.00019 (2000.0) Inc. = 8.43756 +/- 0.00003 q = 1.3388521 +/- 0.0000024 AU e = 0.6946161 +/- 0.0000006 a = 4.3841612 +/- 0.0000027 AU n' = 0.10736786 +/- 0.00000010 P = 9.180 +/- 0.0000084 years A1 = +0.273 +/- 0.024 A2 = +0.02578 +/- 0.00039 T = 1972 Aug. 31.05017 TT Epoch = 1972 Aug. 31.0 TT Peri. = 84.38151 e = 0.6920974 Node = 314.95558 (2000.0) a = 4.3982038 AU Inc. = 9.26002 n'= 0.10685407 q = 1.3542184 AU P = 9.224 years T = 1981 Nov. 27.45398 TT Epoch = 1981 Nov. 12.0 TT Peri. = 84.50891 e = 0.6913241 Node = 314.75586 (2000.0) a = 4.4092262 AU Inc. = 9.24892 n'= 0.10645364 q = 1.3610221 AU P = 9.259 years T = 1991 Feb. 22.72953 TT Epoch = 1991 Mar. 5.0 TT Peri. = 84.81994 e = 0.6916102 Node = 314.44235 (2000.0) a = 4.3941620 AU Inc. = 9.25482 n'= 0.10700153 q = 1.3551146 AU P = 9.211 years The predicted orbit for the 2009 return is as follows: T = 2009 June 14.29558 TT Epoch = 2009 June 18.0 TT Peri. = 96.30456 e = 0.6895439 Node = 300.74140 (2000.0) a = 4.4354426 AU Inc. = 8.95144 n'= 0.10551122 q = 1.3770103 AU P = 9.341 years The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 1973/ 811028 491 0.8- 0.3- 820120 801 1.0- 0.1- 730208 675 0.2+ 1.1- 811029 020 (1.0+ 3.6+) 820125 491 0.9- 0.5- 730209 675 1.0- 0.3+ 811029 491 0.8- 0.3- 820126 491 1.0+ 1.5+ 730210 801 1.4- 2.4+ 811102 801 0.0 0.4- 1991/ 730210 801 1.5+ 1.7+ 811105 707 0.5- 0.5+ 910107 372 0.2- 1.9- 730225 801 1.1+ 0.1- 811115 707 1.5+ 0.4- 910107 372 (5.0- 0.2+) 730225 801 (0.9- 2.8+) 811115 504(78.9+ 30.7+) 910112 372 1.8- 0.9+ 730228 801 (1.1+ 4.1-) 811115 504(76.0+ 32.2+) 910113 372 (0.0 3.6-) 730301 801 1.6+ 0.9+ 811123 801 (0.6+ 2.6+) 910113 372 (3.2- 0.9-) 730326 691 0.4- 0.2- 811125 491 (3.0+ 1.3+) 910113 372 0.2- 0.6- 730326 691 0.0 0.1- 811126 552 0.2+ 0.4- 910113 372 0.6- 0.1- 1981/ 811126 552 (2.6+ 2.7-) 910402 372 1.7+ 0.5+ 810711 801 (2.1- 5.0+) 811126 552 0.5+ 0.1+ 910402 372 1.5+ 1.0+ 810731 801 1.0+ 1.4+ 811126 491 0.4+ 0.2+ 910402 372 0.7- 0.3- 810801 801 0.2+ 0.4- 811127 489 0.6- 0.7+ 2000/ 810802 801 0.6- 1.2- 811127 489 0.9- 0.7+ 001222 696 0.8+ 0.6+ 810805 372 (0.8- 5.0+) 811128 494 0.5+ 0.4- 001222 696 0.9+ 0.1+ 810824 046 0.2+ 1.5+ 811128 494 0.1+ 1.4- 001223 696 0.1+ 0.5+ 810824 046 0.3- 1.5+ 811201 020 (5.6+ 3.2+) 001223 696 0.9+ 0.3+ 810826 801 0.9+ 0.5- 811217 489 1.0+ 0.6+ 001229 867 0.2+ 0.2+ 810828 046 (0.9+ 2.8-) 811217 489 0.5+ 0.3+ 001229 867 0.3+ 0.6+ 810828 046 0.4+ 1.6- 811219 801 (6.4- 0.2+) 001229 867 0.2+ 0.9+ 810901 381 (5.1+ 1.6-) 811222 494 (5.2+ 0.7+) 2001/ 810906 046 0.5+ 1.9+ 811222 489 (4.7+ 3.8+) 010226 360 1.3- 0.1+ 810906 046 1.5- 0.6- 811222 489 0.3+ 0.1- 010226 360 0.4+ 0.1- 810921 046 1.2- 0.4- 811222 494 1.3+ 1.5- 010226 360 0.1+ 1.0- 810925 801 1.3- 1.4+ 811231 489 0.2- 0.9- 010226 867 0.2- 0.3+ 810929 491 1.0- 2.0+ 1982/ 010226 867 0.5- 0.6- 810930 491 2.1+ 1.1- 820117 887 1.3- 1.6- 010226 867 0.3- 0.3- ( ) -------- Rejected Obs.
Director, Computing Section Syuichi Nakano 2006 Apr. 8