OAA computing section circular NK NK678A 51P/Harrington = Nucleus C in 1994
The following improved orbital elements, by S. Nakano, are from 38 observations 1980-1994, 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 +/- 1.13 arc seconds. Epoch = 1994 Sept. 5.0 TT T = 1994 Aug. 23.51567 +/- 0.00463 (m.e.) TT Peri. = 233.45150 +/- 0.00297 Node = 119.26161 +/- 0.00023 (2000.0) Inc. = 8.65595 +/- 0.00006 q = 1.5718729 +/- 0.0000115 AU e = 0.5613858 +/- 0.0000029 a = 3.5837258 +/- 0.0000098 AU n' = 0.14527869 +/- 0.00000059 P = 6.784 +/- 0.0000278 years A1 = +1.605 +/- 0.413 A2 = +0.39496 +/- 0.00311 T = 1980 Dec. 24.57454 TT Epoch = 1980 Dec. 27.0 TT Peri. = 233.05111 e = 0.5557417 Node = 119.62644 (2000.0) a = 3.6115378 AU Inc. = 8.64783 n'= 0.14360376 q = 1.6044558 AU P = 6.863 years T = 1987 Oct. 31.78580 TT Epoch = 1987 Oct. 12.0 TT Peri. = 233.05178 e = 0.5571387 Node = 119.61561 (2000.0) a = 3.6036351 AU Inc. = 8.65396 n'= 0.14407641 q = 1.5959107 AU P = 6.841 years The predicted orbit for the 2001 return is as follows: T = 2001 June 6.74835 TT Epoch = 2001 June 20.0 TT Peri. = 233.59703 e = 0.5619252 Node = 119.17935 (2000.0) a = 3.5796051 AU Inc. = 8.65647 n'= 0.14552962 q = 1.5681348 AU P = 6.773 years The following residuals in seconds of arc are from the above orbital elements: 1980/ 870721 691 1.2- 0.9- 871119 474 0.6+ 0.5+ 800904 323 2.2+ 0.0 870721 691 1.0- 0.5- 871119 474 0.7- 0.3+ 800908 323 (4.4+ 14.5+) 870721 691 0.8- 1.1- 871122 897 0.6+ 0.8+ 800909 323 1.6- 2.3+ 870722 691 1.1+ 1.2- 871122 897 1.5+ 2.7+ 801006 323(17.4- 17.2-) 870722 691 0.1+ 1.2- 871124 323 (4.4- 1.1+) 1987/ 870722 691 1.2+ 0.8- 1994/ 870501 691 1.5+ 0.6+ 870724 323 2.4+ 0.1+ 940613 691 1.0+ 1.3- 870501 691 0.2- 1.9+ 870817 691 0.6+ 0.4+ 940613 691 1.1+ 1.7- 870503 691 0.7- 0.1- 870817 691 0.3+ 0.7+ 941004 691 0.1+ 1.1+ 870503 691 0.9- 0.7+ 870817 691 0.0 0.4+ 941004 691 2.3+ 0.5+ 870503 691 1.1- 0.2- 870818 691 0.8- 1.0+ 941004 691 1.6+ 0.3+ 870503 691 0.1- 0.7- 870818 691 1.2- 0.3+ 941004 691 0.3- 1.5- 870523 691 0.4+ 0.5- 870818 691 1.3- 1.0+ 941005 691 1.5- 1.5- 870523 691 1.0+ 0.3- 870818 691 1.0- 0.6+ 941005 691 1.4- 1.9- 870523 691 0.8+ 0.7- 870920 399 (1.6- 2.9+) 870702 323 (1.1- 4.0+) 870927 399 0.2- 2.6+ ( ) -------- Rejected Obs.
Director, Computing Section Syuichi Nakano 1998 May 1