Nakano Note (Nakano wa Kangaeru noda) NK 2997 151P/Helin
The following improved orbital elements, by S. Nakano, are from 155 observations 1987 to 2015. Perturbations by Mercury to Neptune and three minor planets, Ceres, Pallas and Vesta, were taken into account. The mean residual is +/- 0.59 arc second. The residuals for re-observation in 2015 July from the prediction in NK 2228 (= HICQ 2015) were +23" and +8" with the delta-T correction = -0.016 day. See the previous orbits in NK 684 and NK 2228. Epoch = 2015 Oct. 25.0 TT T = 2015 Oct. 8.07267 +/- 0.00025 (m.e.) TT Peri. = 216.26545 +/- 0.00017 Node = 143.15473 +/- 0.00017 (2000.0) Inc. = 4.71946 +/- 0.00003 q = 2.4737667 +/- 0.0000037 AU e = 0.5721648 +/- 0.0000006 a = 5.7820555 +/- 0.0000021 AU n' = 0.07088930 +/- 0.00000004 P = 13.903 +/- 0.0000076 years T = 1987 Aug. 12.17861 TT Epoch = 1987 July 24.0 TT Peri. = 216.27183 e = 0.5665151 Node = 143.73216 (2000.0) a = 5.9318440 AU Inc. = 4.68656 n'= 0.06822122 q = 2.5713650 AU P = 14.447 years T = 2001 Sept.23.72211 TT Epoch = 2001 Sept. 8.0 TT Peri. = 215.42294 e = 0.5655861 Node = 143.53587 (2000.0) a = 5.8258989 AU Inc. = 4.71685 n'= 0.07009058 q = 2.5308516 AU P = 14.062 years The predicted orbit for the 2029 return is as follows: T = 2029 Aug. 18.14833 TT Epoch = 2029 Aug. 12.0 TT Peri. = 216.05299 e = 0.5723986 Node = 143.04096 (2000.0) a = 5.7827672 AU Inc. = 4.72102 n'= 0.07087621 q = 2.4727195 AU P = 13.906 years The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 1987/ 010823 402 0.3- 0.4- 010926 699 1.6- 0.0 870824 675 (4.9- 2.0-) 010823 402 0.4- 0.2- 010926 699 1.5- 0.6+ 870824 675 (5.0- 0.9-) 010823 402 0.1- 0.1- 011011 704 1.2+ 0.0 870826 675 (5.2- 1.7-) 010824 704 0.9+ 0.7+ 011011 704 0.2+ 0.2+ 870826 675 (5.7- 1.1-) 010824 704 0.7- 0.3+ 011011 704 (0.8- 2.3+) 870917 675 (0.9- 2.7-) 010824 704 1.0+ 0.2- 011011 704 0.2- 0.1+ 870917 675 (3.0+ 0.0 ) 010824 704 0.2- 1.2- 011011 704 0.5- 0.3- 870918 675 0.0 1.4- 010825 504 0.0 0.7+ 011013 704 0.5+ 1.8+ 870918 675 1.3+ 0.6- 010825 504 0.3- 0.5+ 011013 704 (2.0+ 0.2+) 870922 688 0.5- 0.0 010825 504 0.9- 0.1- 011013 704 1.1+ 1.1- 870922 688 0.4- 0.0 010828 360 0.1- 0.2- 011013 704 0.2- 0.8- 870922 688 0.6- 0.3- 010828 360 0.0 0.1- 011013 360 0.4+ 0.4- 870927 691 0.2+ 0.9- 010828 360 0.1- 0.2- 011013 360 0.5+ 0.2- 870927 691 0.6+ 1.4- 010907 699 1.0- 0.5- 011013 867 0.3+ 0.2- 870927 691 0.2+ 0.8- 010907 699 0.2- 1.5+ 011013 867 0.5+ 0.1- 870927 691 0.2+ 0.9- 010907 699 0.9- 1.1+ 011017 644 0.0 0.2+ 871016 691 0.0 0.5- 010907 699 0.6- 0.6+ 011017 644 0.3+ 0.6+ 871016 691 0.4- 0.6- 010912 704 0.4- 1.7+ 011017 644 0.0 0.6+ 871026 688 (0.0 2.8-) 010912 704 0.0 1.2+ 011017 644 0.4+ 0.1- 871026 688 (0.0 2.8-) 010912 704 0.7- 1.0+ 011017 644 0.5+ 0.5+ 871221 691 1.0+ 1.0- 010912 704 0.4+ 0.2+ 011017 644 0.7+ 0.3- 871222 691 (5.5+ 2.0+) 010912 704 0.9- 0.8+ 011117 699 0.2+ 1.0+ 871222 691 (4.5+ 0.9+) 010912 704 0.5- 0.3+ 011117 699 1.1+ 0.3+ 1988/ 010912 704 0.8- 0.9+ 011117 699 0.5+ 0.5+ 880115 691 (3.2+ 0.1-) 010912 704 0.1- 0.1+ 011117 699 0.3+ 0.6+ 880115 691 0.7+ 0.1- 010912 704 1.3- 0.2- 011117 608 0.4- 1.3- 880115 688 (3.2+ 0.9-) 010912 704 0.2- 0.1- 011117 608 0.6- 0.9- 880115 688 (2.7+ 0.6-) 010918 699 1.7- 1.0+ 011117 608 0.6+ 0.8- 880121 691 1.3+ 0.3- 010918 699 0.9- 0.4+ 011120 704 0.1- 0.7- 880121 691 1.6- 0.2+ 010918 699 1.3- 0.4+ 011120 704 0.5+ 0.5- 880212 691 1.6+ 1.4+ 010918 699 1.4- 1.2+ 011120 704 0.2+ 0.0 880212 691 (3.9+ 0.2+) 010918 360 0.4+ 0.0 011120 704 1.5+ 0.6- 880213 691 1.7+ 0.8+ 010918 360 0.2+ 0.0 011120 704 0.5+ 1.4+ 2001/ 010918 360 0.2+ 0.1+ 011205 704 (2.7+ 0.0 ) 010620 493 0.2+ 0.6+ 010919 704 0.7+ 0.7+ 011205 704 0.2- 0.2+ 010620 493 0.1+ 0.7+ 010919 704 0.7+ 0.1- 011205 704 0.7- 0.5+ 010621 493 0.3+ 0.0 010919 704 0.4+ 0.5+ 011205 704 1.8+ 0.2- 010621 493 1.0+ 0.8+ 010919 704 0.4+ 0.1+ 011217 699 0.3- 0.8+ 010621 493 1.0+ 0.5+ 010919 704 1.2- 0.1- 011217 699 0.2+ 0.2+ 010622 493 0.2+ 0.2+ 010921 704 0.7+ 0.4+ 011217 699 0.3- 0.7+ 010622 493 1.3+ 0.3- 010921 704 1.4- 0.1+ 011217 699 0.9+ 1.8- 010622 493 0.5+ 0.2+ 010921 704 1.0+ 0.1+ 2015/ 010722 704 1.0+ 0.1- 010921 704 1.3- 0.0 150723 F51 0.0 0.1- 010722 704 0.7+ 0.8+ 010921 704 0.9+ 0.3+ 150723 F51 0.1+ 0.0 010722 704 0.2+ 0.8+ 010921 704 1.5- 0.2- 150723 F51 0.2+ 0.0 010722 704 0.2+ 1.0+ 010921 704 0.2+ 0.0 150723 F51 0.2+ 0.0 010724 360 0.1+ 0.5+ 010921 704 1.5- 0.4+ 150727 F52 0.1+ 0.1- 010724 360 0.2- 0.4+ 010921 704 0.2+ 0.0 150727 F52 0.2+ 0.1- 010724 360 0.1+ 0.5+ 010921 704 (2.2- 0.2+) 150727 F52 0.1+ 0.0 010813 170 0.5- 1.7- 010924 704 1.1+ 0.1+ 150727 F52 0.2+ 0.1- 010813 170 0.7- 0.8- 010924 704 0.2- 0.8- 150730 F51 0.0 0.1- 010815 046 0.2- 0.1- 010924 704 0.2+ 0.1- 150730 F51 0.1+ 0.3- 010815 046 0.3+ 0.2- 010924 704 0.1- 0.5- 150730 F51 0.2- 0.3- 010815 046 0.5- 0.3- 010924 704 0.7- 0.8- 150730 F51 0.0 0.1- 010815 046 0.1- 0.5- 010925 644 0.6+ 0.8+ 150818 W96 0.6- 0.1- 010815 046 0.0 0.1- 010925 644 0.4+ 0.6+ 150818 W96 0.5- 0.2- 010816 829 0.6- 0.2- 010925 644 0.1+ 0.7+ 150822 A77 0.8- 0.3- 010816 829 0.7- 0.2+ 010926 699 0.3- 0.7+ 150822 A77 0.8- 0.4- 010816 829 0.5- 0.2- 010926 699 1.2- 0.4+ 150822 A77 0.9- 0.1- ( ) -------- Rejected Obs.
Associate of the CBAT Syuichi Nakano 2015 Sept. 11