OAA computing section circular NK 920 79P/du Toit-Hartley
The following improved orbital elements, by S. Nakano, are from 61 observations 1982 (Nucleus A observations) and 1986 to 2003, 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 +/- 1.08 arc seconds. See a prediction on NK 706 (= MPC 40670) with delta-T correction = +0.053 day and also NK 479, NK 521 and NK 617. Epoch = 2003 Feb. 10.0 TT T = 2003 Feb. 15.37921 +/- 0.00244 (m.e.) TT Peri. = 253.07414 +/- 0.00231 Node = 307.97156 +/- 0.00050 (2000.0) Inc. = 2.89446 +/- 0.00002 q = 1.2299757 +/- 0.0000032 AU e = 0.5941118 +/- 0.0000011 a = 3.0303315 +/- 0.0000037 AU n' = 0.18683957 +/- 0.00000035 P = 5.275 +/- 0.0000098 years A1 = +0.194 +/- 0.099 A2 = +0.01117 +/- 0.00039 T = 1982 Mar. 30.44329 TT Epoch = 1982 Mar. 12.0 TT Peri. = 251.57496 e = 0.6023282 Node = 309.38245 (2000.0) a = 3.0043651 AU Inc. = 2.94414 n'= 0.18926705 q = 1.1947512 AU P = 5.207 years T = 1987 June 14.00950 TT Epoch = 1987 June 14.0 TT Peri. = 251.56037 e = 0.6012340 Node = 309.34783 (2000.0) a = 3.0069259 AU Inc. = 2.94249 n'= 0.18902533 q = 1.1990597 AU P = 5.214 years [ T = 1992 Aug. 27.62348 TT Epoch = 1992 Sept.15.0 TT Peri. = 251.47439 e = 0.6016245 Node = 309.35389 (2000.0) a = 3.0051029 AU Inc. = 2.94274 n'= 0.18919735 q = 1.1971595 AU P = 5.209 years ] [ T = 1997 Nov. 14.54784 TT Epoch = 1997 Nov. 8.0 TT Peri. = 251.61876 e = 0.6007801 Node = 309.23961 (2000.0) a = 3.0075745 AU Inc. = 2.93947 n'= 0.18896418 q = 1.2006836 AU P = 5.216 years ] The predicted orbit for the 2008 return is as follows: T = 2008 May 28.45355 TT Epoch = 2008 May 14.0 TT Peri. = 253.27879 e = 0.5940123 Node = 307.84038 (2000.0) a = 3.0308307 AU Inc. = 2.89302 n'= 0.18679341 q = 1.2304799 AU P = 5.276 years The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 1982/ 820422 707 0.8- 0.2+ 870125 691 0.6- 0.8- 820205 413 1.9- 1.6- 820423 474 0.2- 0.8+ 870327 691 2.2+ 0.1- 820206 413 (0.3+ 4.4-) 820423 474 0.5+ 1.1+ 870327 691 1.7+ 0.2+ 820207 413 (2.2- 6.4+) 820525 809 0.6+ 2.1- 870327 691 1.7+ 0.4- 820216 413 1.6- 3.3+ 820526 809 (2.4+ 4.7-) 870328 691 1.8+ 0.5- 820217 372 1.8- 1.0- 820526 809 (3.6+ 4.3-) 870328 691 0.5+ 0.6- 820218 707 1.6+ 1.5- 820528 474 0.0 0.1- 870328 691 0.5+ 0.8- 820219 474 (4.5+ 3.7+) 820528 474 0.5+ 0.1+ 870501 691 1.7+ 0.1+ 820219 474 (4.0+ 2.1+) 820623 474 0.4+ 0.2- 870501 691 2.0+ 0.6- 820219 413 0.1+ 1.1+ 820623 474 0.2+ 0.4+ 870501 691 0.8+ 0.1- 820219 413 0.8- 0.5- 1986/ 870525 691 1.6- 0.4- 820220 688(10.4- 2.6-) 861227 691 0.4- 0.2+ 870525 691 1.0- 0.2+ 820220 688(16.7- 6.8+) 861227 691 0.7- 0.5+ 870525 691 1.4- 0.1- 820220 474 0.9+ 2.5+ 861227 691 0.2- 0.5+ 2003/ 820222 474 0.2+ 2.1- 861228 691 0.5- 0.4- 030304 844 (2.5+ 1.3-) 820222 474 0.9+ 1.6- 861228 691 0.5- 0.7+ 030304 844 2.0- 0.3- 820224 707 0.9+ 1.5- 861228 691 0.9- 1.2+ 030304 844 0.7+ 0.8- 820224 707 0.2+ 1.4- 1987/ 030304 844 0.0 1.1- 820225 372 0.2- 2.6+ Y 870103 691 0.1+ 0.3- 030304 844 1.9+ 1.0- 820228 675 (3.9+ 2.1-) 870103 691 0.5- 0.2- 030305 844 0.1+ 1.2- 820228 675 1.3+ 2.1+ 870103 691 0.1- 0.1+ 030305 844 0.9+ 1.5- 820321 474 0.6- 0.5+ 870103 691 0.0 0.1- 030305 844 0.2- 0.8- 820321 474 1.0+ 0.0 870103 691 0.0 0.3- 030305 844 0.4- 1.3- 820327 474 1.0- 1.0+ 870125 691 0.9- 1.1- 030305 844 1.6- 1.2- 820327 474 0.3- 0.9+ 870125 691 0.9- 1.1- 030305 844 1.4+ 1.1- ( ) -------- Rejected Obs.
Director, Computing Section Syuichi Nakano 2003 Mar. 17