Nakano Note (Nakano wa Kangaeru noda) NK 4550 A/2009 KF37
The following improved orbital elements, by S. Nakano, are from 65 observations 2001 to 2017, Perturbations by Mercury to Neptune and three minor planets, Ceres, Pallas and Vesta, were taken into account. The mean residual is +/- 0.69 arc second. Pan-STARRS reports that the object has comet nature on their frames taken on the three nights 2017 April-May. Also Hidetaka Sato, Tokyo, reports in 2017 that "The cometary activity of this object was found when it was discovered by Palomar Transient Survey. But on 2017 Apr. 28, the object appeared stellar and about 1 mag fainter than predicted. On 2017 July 21 the object appeared softer than nearby stars." Sato gives CCD total magnitudes 20.9 and 19.9, respectively. The object has passed 0.95 AU from Jupiter on 2012 Jan. 15 UT. Epoch = 2017 Oct. 14.0 TT T = 2017 Sept.26.40024 +/- 0.00020 (m.e.) TT Peri. = 144.02114 +/- 0.00012 Node = 111.95056 +/- 0.00009 (2000.0) Inc. = 11.39996 +/- 0.00001 q = 2.8160638 +/- 0.0000025 AU e = 0.3127901 +/- 0.0000006 a = 4.0978222 +/- 0.0000053 AU n' = 0.11881586 +/- 0.00000023 P = 8.295 +/- 0.0000161 years T = 2001 Oct. 7.87748 TT Epoch = 2001 Oct. 18.0 TT Peri. = 136.52971 e = 0.3411148 Node = 118.44435 (2000.0) a = 3.9480062 AU Inc. = 11.20646 n'= 0.12564272 q = 2.6012827 AU P = 7.845 years T = 2009 Aug. 9.14007 TT Epoch = 2009 July 28.0 TT Peri. = 136.66020 e = 0.3422538 Node = 118.39442 (2000.0) a = 3.9378848 AU Inc. = 11.21636 n'= 0.12612743 q = 2.5901286 AU P = 7.814 years The predicted orbit for the 2026 return is as follows: T = 2026 Jan. 17.63843 TT Epoch = 2025 Dec. 31.0 TT Peri. = 143.94898 e = 0.3107494 Node = 111.94162 (2000.0) a = 4.1133185 AU Inc. = 11.38827 n'= 0.11814506 q = 2.8351074 AU P = 8.342 years The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 2001/ 090601 I41 1.9- 0.1+ 160403 F51 0.2- 0.2- 010523 699 0.2+ 0.4- 090601 I41 0.9- 0.2+ 2017/ 010523 699 0.7+ 0.6- 090601 I41 1.6- 0.1- 170406 F51 0.2+ 0.3- 010523 699 0.2+ 0.1- 090601 I41 1.4- 0.2- 170406 F51 0.1+ 0.2- 010523 699 1.4+ 0.2- 090601 I41 1.3- 0.2+ 170406 F51 0.1+ 0.6- 010618 699 0.1+ 0.4+ 090601 I41 1.4- 0.0 170426 F51 0.0 0.2- 010618 699 1.4+ 0.8- 090601 I41 1.1- 0.2- 170426 F51 0.0 0.1- 010618 699 0.6- 0.4+ 090714 I41 0.8- 0.2- 170426 F51 0.0 0.3- 010618 699 0.3- 0.9- 090714 I41 0.3+ 0.2- 170426 F51 0.0 0.3- 2009/ 2015/ 170428 F51 0.1- 0.4- 090527 I41 1.3- 0.2- 150116 F51 0.6+ 0.1+ 170428 F51 0.0 0.4- 090527 I41 1.1- 1.0- 150116 F51 0.5+ 0.1- 170428 F51 0.0 0.2- 090527 I41 0.8- 0.3+ 150116 F51 0.3+ 0.1+ 170428 F51 0.2+ 0.3- 090527 I41 1.5- 0.1+ 150116 F51 0.4+ 0.1- 170428 Q62 0.4+ 0.5- 090527 I41 1.2- 0.1- 2016/ 170428 Q62 0.1+ 0.9- 090527 I41 1.0- 0.1+ 160203 F51 0.3+ 0.2+ 170518 F51 0.2+ 0.3- 090527 I41 1.3- 0.4+ 160203 F51 0.4- 0.4+ 170518 F51 0.1+ 0.4- 090527 I41 1.8- 0.3+ 160205 F51 0.6- 0.2- 170518 F51 0.0 0.2- 090530 691 1.9- 0.2+ 160205 F51 0.3- 0.4- 170518 F51 0.0 0.4- 090530 691 1.8- 0.4+ 160205 F51 0.4- 0.3- 170721 Q62 0.0 0.2- 090530 691 1.9- 0.0 160206 F51 0.4- 0.0 170721 Q62 0.2- 0.0 090601 I41 1.2- 0.1+ 160206 F51 0.2+ 0.2- 170721 Q62 0.2+ 0.3- 090601 I41 1.9- 0.3+ 160311 F51 0.2- 0.2- 090601 I41 1.2- 0.2- 160325 F51 0.1- 0.5+ ( ) -------- Rejected Obs.
Associate of the CBAT Syuichi Nakano 2021 Oct. 1