OAA computing section circular NK 1193 26P/Grigg-Skjellerup
The following improved orbital elements, by S. Nakano, are from 207 observations 1952 to 1997, 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 +/- 0.88 arc second. See previous orbits in NK 700 and NK700o. Epoch = 1997 Aug. 20.0 TT T = 1997 Aug. 30.30329 +/- 0.00046 (m.e.) TT Peri. = 359.33153 +/- 0.00008 Node = 213.30926 +/- 0.00004 (2000.0) Inc. = 21.08676 +/- 0.00002 q = 0.9968107 +/- 0.0000006 AU e = 0.6638055 +/- 0.0000001 a = 2.9649823 +/- 0.0000007 AU n' = 0.19305049 +/- 0.00000006 P = 5.105 +/- 0.0000018 years A1 = +0.005 +/- 0.002 A2 = -0.00113 +/- 0.00002 T = 1952 Mar. 11.16104 TT Epoch = 1952 Mar. 9.0 TT Peri. = 356.34669 e = 0.7035963 Node = 216.09401 (2000.0) a = 2.8866634 AU Inc. = 17.62240 n'= 0.20096010 q = 0.8556178 AU P = 4.904 years T = 1957 Feb. 2.63346 TT Epoch = 1957 Feb. 11.0 TT Peri. = 356.31396 e = 0.7036389 Node = 216.09943 (2000.0) a = 2.8859730 AU Inc. = 17.63051 n'= 0.20103222 q = 0.8552901 AU P = 4.903 years T = 1961 Dec. 31.35773 TT Epoch = 1962 Jan. 16.0 TT Peri. = 356.36925 e = 0.7029769 Node = 216.07464 (2000.0) a = 2.8878584 AU Inc. = 17.61504 n'= 0.20083538 q = 0.8577608 AU P = 4.908 years T = 1967 Jan. 16.47515 TT Epoch = 1967 Jan. 30.0 TT Peri. = 359.15946 e = 0.6624352 Node = 213.39439 (2000.0) a = 2.9711444 AU Inc. = 21.04405 n'= 0.19245023 q = 1.0029538 AU P = 5.121 years T = 1972 Mar. 2.65281 TT Epoch = 1972 Feb. 13.0 TT Peri. = 359.27076 e = 0.6628374 Node = 213.36071 (2000.0) a = 2.9698073 AU Inc. = 21.06199 n'= 0.19258021 q = 1.0013080 AU P = 5.118 years T = 1977 Apr. 11.00064 TT Epoch = 1977 Apr. 7.0 TT Peri. = 359.31068 e = 0.6647053 Node = 213.35378 (2000.0) a = 2.9627253 AU Inc. = 21.09842 n'= 0.19327113 q = 0.9933860 AU P = 5.100 years T = 1982 May 14.99662 TT Epoch = 1982 May 31.0 TT Peri. = 359.31672 e = 0.6656800 Node = 213.34135 (2000.0) a = 2.9589839 AU Inc. = 21.13128 n'= 0.19363782 q = 0.9892476 AU P = 5.090 years T = 1987 June 18.04603 TT Epoch = 1987 June 14.0 TT Peri. = 359.30556 e = 0.6647125 Node = 213.33560 (2000.0) a = 2.9625420 AU Inc. = 21.10051 n'= 0.19328907 q = 0.9933032 AU P = 5.099 years T = 1992 July 22.13775 TT Epoch = 1992 Aug. 6.0 TT Peri. = 359.26493 e = 0.6643253 Node = 213.34040 (2000.0) a = 2.9632550 AU Inc. = 21.09897 n'= 0.19321931 q = 0.9946898 AU P = 5.101 years [ T = 1997 Aug. 30.30329 TT Epoch = 1997 Aug. 20.0 TT Peri. = 359.33153 e = 0.6638055 Node = 213.30926 (2000.0) a = 2.9649823 AU Inc. = 21.08676 n'= 0.19305049 q = 0.9968107 AU P = 5.105 years ] The predicted orbit for the 2008 return is as follows: T = 2008 Mar. 23.68635 TT Epoch = 2008 Apr. 4.0 TT Peri. = 1.71474 e = 0.6330014 Node = 211.70637 (2000.0) a = 3.0428239 AU Inc. = 22.35650 n'= 0.18569014 q = 1.1167122 AU P = 5.308 years The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 1952/ 820624 801 1.7- 1.5- 920109 695 0.7+ 0.0 520309 081 (3.4+ 4.8+) 820625 801 0.6- 0.5+ 920109 695 0.5+ 0.2- 520325 081 (2.9+ 5.6+) 820627 801 0.3- 0.4+ 920109 695 0.6+ 0.1+ 520421 711 2.3+ 0.4+ 820710 707 1.0- 1.4- 920109 695 0.6+ 0.0 1956/ 820719 801 1.2- 0.1+ 920109 695 0.7+ 0.1- 561229 388 0.4+ 0.4- 820723 801 0.0 1.6+ 920109 695 1.1+ 0.2+ 1957/ 820818 801 2.0- 0.1+ 920203 493 1.0- 0.3+ 570102 675 0.1+ 2.1- 1986/ 920203 493 1.4- 1.0+ 570107 388 (4.8+ 3.2-) 860812 493 0.7+ 0.0 920203 493 0.9- 0.2+ 1961/ 860813 493 0.3+ 0.1+ 920204 493 0.7- 0.3+ 611109 371 1.5- 1.4+ 860813 493 0.2+ 0.1- 920321 493 0.2+ 0.3- 611110 689 1.3- 0.4+ 860813 493 0.2+ 0.2- 920321 493 0.1+ 0.3- 611118 689 0.7+ 0.6+ 860813 493 0.0 0.4- 920322 493 0.1+ 0.5- 611204 689 0.3+ 0.3+ 1987/ 920322 493 0.4+ 0.3- 1966/ 870103 691 0.7+ 1.1- 920517 493 0.4+ 0.4+ 661219 675 (2.5+ 3.0-) 870103 691 0.2+ 1.9- 920524 413 0.6- 2.0+ 661219 675 0.8+ 0.7+ 870103 691 0.1- 1.3- 920524 413 0.5- 0.6- 1972/ 870131 807 (3.4- 1.5-)Y 920524 413 0.0 0.2+ 720126 805 (7.5- 3.8-) 870131 807 0.4- 1.4+ Y 920529 474 0.0 1.0+ 720126 805 (6.9- 5.9-) 870201 807 (5.3- 3.9-)Y 920531 474 0.3+ 1.5+ 720212 691 0.2- 0.6- 870201 807 (4.3- 3.2-)Y 920531 474 2.2+ 0.5+ 720212 691 0.0 0.3- 870202 807 (7.0- 3.9-)Y 920619 474 0.3+ 0.3+ 720513 693 0.5- 1.2+ 870202 807 (5.3- 3.4-)Y 920619 474 1.4- 1.8+ 720513 693 0.1- 0.1- 870227 413 0.5- 0.7+ 920619 413 0.1- 0.1+ 720518 691 0.5+ 0.6+ 870302 691 1.6+ 0.4+ 920619 413 0.2+ 0.2- 720713 691 0.5- 0.5+ 870302 691 1.9+ 0.1- 920619 413 0.2+ 0.2- 720713 691 1.3- 0.6+ 870302 691 1.4+ 0.3+ 920620 474 0.2+ 0.3- 720814 691 1.1- 0.1- 870302 691 1.5+ 0.7+ 920620 474 0.7- 1.4+ 720814 691 1.1- 0.4- 870302 691 1.1+ 0.4+ 920623 474 0.2- 1.3+ 1977/ 870302 691 0.9+ 0.5+ 920623 474 1.8+ 2.0+ 770121 323 (0.8+ 3.8+) 870303 691 0.2+ 0.0 920624 474 0.5- 0.2+ 770125 323 0.9- 1.0+ 870303 691 0.3+ 0.9+ 920624 474 1.4- 0.3+ 770126 485 (3.4- 3.1-) 870303 691 0.1- 0.2- 920624 493 0.6+ 1.2+ 770126 485 0.3- 1.6- 870327 691 0.9+ 1.2- 920624 493 0.7+ 0.6+ 770127 323 0.8- 0.8- 870327 691 0.8+ 0.9- 920625 474 0.8+ 0.9+ 770309 323 1.0+ 0.5- 870327 691 1.0+ 0.9- 920625 474 1.8+ 0.4+ 770311 485 1.3+ 1.8- 870425 691 0.1+ 1.4- 920627 474 (2.8- 0.9+) 770311 485 (0.7+ 2.5-) 870425 691 0.1+ 1.4- 920627 474 0.7- 1.2+ 770314 323 0.6+ 1.6+ 870519 323 (0.9+ 8.5+) 920627 474 0.0 0.9+ 770316 323 (3.8+ 1.6-) 870521 493 1.0- 0.2+ 920628 474 (1.3- 2.8+) 770317 323 1.1- 0.1- 870528 493 0.1+ 0.1+ 920628 474 1.2+ 0.7+ 770318 323 1.7- 0.2- 870603 493 0.3- 0.4+ 920628 474 0.5- 2.2+ 770319 485 (3.6+ 3.1-) 870604 493 0.3- 0.6+ 920629 809 0.5+ 0.1- 770319 485 1.0+ 1.8- 870605 493 0.0 0.1+ 920629 809 0.1- 0.1- 770321 323 1.6+ 1.4+ 870621 474 0.6- 0.2+ 920630 474 (3.3- 0.8-) 770325 323 (1.8+ 6.0-) 870621 474 1.2- 0.2+ 920630 474 (2.4- 3.2-) 770325 323 1.0+ 0.8- 870622 707 1.7- 0.2+ 920701 474 (2.2+ 2.6-) 770330 323 (6.4+ 4.0+) 870622 707 0.7- 0.0 920701 474 0.7- 0.1- 770401 807 1.4+ 1.2+ 870622 474 0.2- 0.4+ 920705 413 0.1- 0.2- 770401 807 (3.1+ 4.5+) 870622 474 0.6+ 0.2- 920705 413 0.0 0.1- 770401 807 (3.9+ 1.7-) 870622 474 0.0 0.0 920705 809 0.0 0.0 770416 801 1.4+ 1.0+ 870628 707 1.2+ 1.1+ 920706 474 0.8- 1.5+ 770416 882 2.3- 2.1- 870628 707 0.1+ 0.4+ 920706 474 (3.2- 1.3+) 770416 882 (1.6- 2.7+) 870716 897 (3.7- 10.8+) 920706 474 0.0 0.8- 770420 372 (4.0+ 6.3+)Y 870718 323 1.0- 2.1+ 920709 809 0.5+ 0.2+ 770420 882 (6.9+ 0.2-) 870720 493 0.7+ 0.1- 920710 809 0.1+ 0.2+ 770420 882 (2.7+ 1.7+) 870728 801 0.3- 0.1- 920710 809 0.5+ 0.3+ 770421 879 1.4+ 2.1+ Y 870804 493 0.5- 0.2- 920710 809 0.1+ 0.1+ 770422 805 (2.5+ 3.4+) 870813 474 (4.1- 0.3+) 920722 323 (2.7- 4.8+) 770422 485 2.2+ 1.7- 870813 474 0.4- 0.5+ 920804 493 0.2- 0.4- 770422 485 1.6+ 2.2- 870818 691 2.1+ 0.6- 920804 493 0.3- 0.3- 770422 485 0.5+ 0.8+ 870818 691 2.2+ 0.3- 920804 493 0.6- 0.4- 770422 323 0.5+ 0.6+ 870818 691 (2.8+ 0.0 ) 920816 323 0.5+ 0.5+ 770428 882 (2.5+ 1.8+) 870821 801 (0.2+ 2.6+) 920823 413 0.4- 0.7- 770428 882 (0.3- 2.6-) 870926 474 0.3+ 1.0+ 920823 413 0.2- 0.7- 770513 993 1.0- 2.4+ 870926 474 0.4- 2.4- 920906 413 0.1- 0.5- 770517 801 0.7- 0.2- 870927 691 0.0 1.4- 920906 413 1.0- 0.2- 770520 993 (4.3+ 0.5-) 870927 691 0.0 1.3- 920923 493 0.5- 0.9- 770520 879 (3.6- 2.1+) 1988/ 921012 413 1.5- 0.4+ 770616 801 0.8- 0.2- 880911 568 (2.9- 1.2+) 921012 413 0.7- 0.2+ 770810 801 (3.6- 0.5+) 880911 568 (3.0- 1.2+) 1993/ 1982/ 1989/ 930914 493 0.2+ 0.5- 820115 675 0.4+ 0.2- 891227 568 (3.1+ 0.8+) 930915 493 0.8- 0.5- 820116 675 0.7- 0.4+ 1991/ 930915 493 0.4- 0.1+ 820323 801 0.4- 0.4- 910909 493 1.0+ 0.7- 930916 493 0.6+ 0.9+ 820326 801 0.2+ 0.6+ 910912 493 0.5+ 0.8- 930916 493 0.4- 0.5- 820401 675 0.3- 0.2- 910912 493 0.8+ 0.6- 930916 493 0.4- 0.4- 820411 707 0.3- 0.3+ 911108 695 0.9+ 1.1- 930917 493 0.4- 0.7- 820413 801 0.0 0.6+ 911108 695 0.8+ 1.0- 1996/ 820419 801 0.4- 0.3- 911108 695 0.9+ 0.9- 961214 691 0.4- 0.2+ 820429 801 0.5- 0.4- 911108 695 1.0+ 1.0- 961214 691 0.8- 0.6+ 820519 801 0.5+ 0.4+ 911203 493 0.0 0.2+ 961215 691 0.7- 0.1- 820613 707 0.5+ 0.9- 911203 493 0.0 0.4+ 961215 691 0.7- 0.0 820614 372 0.1+ 0.1- 1992/ 961215 691 0.6- 0.2+ 820618 491 0.3- 1.0- 920109 695 0.7+ 0.3- 1997/ 820619 491 2.4- 0.6+ 920109 695 0.6+ 0.1- 970117 691 1.7- 0.0 820619 801 0.7+ 0.8- 920109 695 0.8+ 0.2- 970117 691 1.4- 0.3+ 820619 801 0.9+ 2.1- 920109 695 0.7+ 0.0 970117 691 1.6- 0.4+ 820621 801 1.8+ 0.8+ 920109 695 0.7+ 0.2- 971027 897 (0.3- 3.1-) 820623 801 1.7+ 0.5+ 920109 695 0.7+ 0.0 971027 897 0.0 0.7+ ( ) -------- Rejected Obs.
Director, Computing Section Syuichi Nakano 2005 July 4