Nakano Note (Nakano wa Kangaeru noda) NK 4646 P/2020 B4 (Sheppard)
The following improved orbital elements, by S. Nakano, are from 14 observations 2019 Nov. 5 to 2021 Feb. 7. Perturbations by Mercury to Neptune and three minor planets, Ceres, Pallas and Vesta, were taken into account. The mean residual is +/- 0.23 arc second. The comet has passed 0.52 AU from Saturn on 1968 July. Also comet has passed near close to 2010 RQ8 on 2010 Sept. 2-3. Epoch = 2021 Dec. 12.0 TT T = 2021 Nov. 22.82663 +/- 0.22504 (m.e.) TT Peri. = 342.30722 +/- 0.01576 Node = 185.98045 +/- 0.00041 (2000.0) Inc. = 11.60737 +/- 0.00007 q = 6.4399508 +/- 0.0001639 AU e = 0.1917884 +/- 0.0000344 a = 7.9681496 +/- 0.0003949 AU n' = 0.04381954 +/- 0.00000326 P = 22.492 +/- 0.0016722 years (+/- 0.61 day) The predicted orbit for the 2044 return is as follows: T = 2044 June 27.91784 TT Epoch = 2044 July 4.0 TT Peri. = 342.98034 e = 0.1913550 Node = 185.94184 (2000.0) a = 7.9575086 AU Inc. = 11.61232 n'= 0.04390747 q = 6.4347996 AU P = 22.447 years The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 2019/ 200127 807 0.0 0.0 210207 F51 0.2+ 0.1+ 191105 F52 0.2+ 0.5- 200204 F52 0.2+ 0.5+ 210207 F51 0.0 0.4- 191125 F52 0.2+ 0.0 200211 W84 0.1+ 0.1- 210207 F51 0.2- 0.1+ 191129 F52 0.2- 0.4+ 200323 F51 0.3- 0.1+ 210207 F51 0.0 0.1+ 2020/ 200512 F52 0.2+ 0.5- 210207 F51 0.0 0.1+ 200126 807 0.4- 0.1- 2021/ ( ) -------- Rejected Obs.
Associate of the CBAT Syuichi Nakano 2022 Feb. 17