Nakano Note (Nakano wa Kangaeru noda) NK 3843 P/2018 Y2 (Africano)
The following improved orbital elements, by S. Nakano, are from 75 observations 2018 Dec. 10 to 2019 Mar. 21. Perturbations by Mercury to Neptune and three minor planets, Ceres, Pallas and Vesta, were taken into account. The mean residual is +/- 0.48 arc second. Epoch = 2018 Dec. 28.0 TT T = 2019 Jan. 2.70259 +/- 0.13152 (m.e.) TT Peri. = 162.51471 +/- 0.02008 Node = 297.26510 +/- 0.00075 (2000.0) Inc. = 11.68027 +/- 0.00053 q = 3.8932853 +/- 0.0000725 AU e = 0.4793779 +/- 0.0000195 a = 7.4781413 +/- 0.0003127 AU n' = 0.04819629 +/- 0.00000302 P = 20.450 +/- 0.0012829 years (+/- 0.47 day) The predicted orbit for the 2039 return is as follows: T = 2039 May 24.75723 TT Epoch = 2039 May 12.0 TT Peri. = 162.30763 e = 0.4799011 Node = 297.20427 (2000.0) a = 7.4864908 AU Inc. = 11.67598 n'= 0.04811568 q = 3.8937153 AU P = 20.484 years The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 2018/ 181231 K88 0.3+ 0.0 190106 T08 1.3- 1.0+ 181210 G96 0.1+ 0.1+ 2019/ 190106 T08 0.9- 0.0 181210 G96 0.1+ 0.1+ 190101 G40 0.9- 0.0 190106 157 0.4+ 0.1- 181210 G96 0.1+ 0.3+ 190101 G40 0.4- 0.4- 190106 157 0.1- 0.3+ 181210 G96 0.1+ 0.1+ 190101 H06 0.4- 0.1- 190106 157 0.1+ 0.2- 181217 D29 0.2- 0.7+ 190101 H06 0.2- 0.0 190108 G96 0.3- 0.0 181217 D29 0.1- 0.5+ 190101 C77 0.5- 0.2- 190108 G96 0.1+ 0.1- 181217 D29 0.4- 0.3+ 190101 C77 0.1- 0.5+ 190108 G96 0.2- 0.2- 181231 G96 0.2- 0.0 190101 C77 0.1+ 0.2- 190108 G96 0.4- 0.1- 181231 G96 0.1- 0.2- 190101 B49 0.2- 0.3- 190115 G96 0.2+ 0.2- 181231 G96 0.2- 0.0 190101 B49 0.1- 0.3+ 190115 G96 0.0 0.1- 181231 G96 0.0 0.0 190101 B49 0.1- 0.1+ 190115 G96 0.2- 0.0 181231 G96 0.0 0.1+ 190101 Z80 1.0- 0.7- 190115 G96 0.0 0.1+ 181231 G96 0.0 0.1+ 190101 Z80 0.7- 0.4- 190129 A71 0.3+ 0.8+ 181231 G96 0.3- 0.1+ 190101 Z80 0.4+ 1.2- 190129 A71 0.1+ 0.5+ 181231 G96 0.3- 0.2- 190101 Z80 1.0+ 0.9- 190129 A71 0.4- 0.8+ 181231 G96 0.3- 0.2+ 190101 106 0.3+ 0.1- 190202 H06 0.0 0.4+ 181231 G96 0.9+ 0.2+ 190102 106 0.8+ 0.6- 190202 H06 0.1+ 0.7+ 181231 P93 0.3- 0.4+ 190102 106 0.4+ 0.4- 190306 G96 0.9- 0.8+ 181231 P93 0.9+ 0.4- 190102 568 0.3+ 0.0 190306 G96 0.2+ 0.2+ 181231 P93 1.0+ 0.9+ 190102 568 0.3+ 0.1- 190306 G96 0.4+ 0.1+ 181231 L01 1.0- 0.4+ 190102 568 0.3+ 0.1- 190306 G96 1.0+ 0.3- 181231 L01 0.6- 0.0 190104 349 0.8- 0.3+ 190321 215 0.4- 0.3+ 181231 L01 0.5- 0.0 190104 349 0.4- 0.4- 190321 215 0.0 0.5- 181231 L01 0.2- 0.0 190106 T08 1.9- 0.5+ 190321 215 0.0 1.3- 181231 K88 0.2- 0.0 190106 T08 0.8- 0.6- ( ) -------- Rejected Obs.
Associate of the CBAT Syuichi Nakano 2019 June 10