Nakano Note (Nakano wa Kangaeru noda) NK 4487 C/2021 C4 (ATLAS)
The following improved orbital elements, by S. Nakano, are from 140 observations 2021 Feb. 12 to June 9. Perturbations by Mercury to Neptune and three minor planets, Ceres, Pallas and Vesta, were taken into account. The mean residual is +/- 0.47 arc second. The comet has passed 3.84 AU from Uranus on 2011 Dec. 7 and 4.15 AU from Jupiter on 2020 Mar. 10 UT. See an orbit in CBET 4937. Epoch = 2021 Jan. 26.0 TT T = 2021 Jan. 17.01779 +/- 0.02731 (m.e.) TT Peri. = 320.22874 +/- 0.00342 Node = 194.27880 +/- 0.00062 (2000.0) Inc. = 132.83910 +/- 0.00085 q = 4.5040950 +/- 0.0000883 AU e = 0.9988169 +/- 0.0001444 1/a = +0.0002627 +/- 0.0000321 1/AU origin = +0.000335 (Q= 6) future = +0.000543 The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 2021/ 210305 W85 0.2- 0.2+ 210417 T05 0.2+ 0.2- 210212 T05 0.4- 0.4- 210305 W85 0.0 0.6+ 210417 Q62 0.3+ 0.1- 210212 T05 0.5- 0.3- 210307 Q64 0.5- 0.5+ 210417 Q62 0.3+ 0.2+ 210212 T05 0.3+ 1.1- 210307 Q64 0.3- 0.3+ 210417 Q62 0.4+ 0.1+ 210212 T05 1.1- 0.6- 210307 Q64 0.4- 0.3+ 210419 T08 0.5+ 0.2- 210213 807 0.2+ 0.0 210307 Q64 0.3- 0.3+ 210419 T08 0.3+ 0.3- 210213 807 0.2- 0.0 210311 W87 0.4- 0.0 210419 T08 0.6+ 0.2- 210213 807 0.4+ 0.2+ 210311 W87 0.1- 0.2+ 210422 E85 0.9+ 1.0- 210213 807 0.3- 0.1- 210311 W87 0.3- 0.2+ 210422 E85 0.2- 0.2+ 210213 807 0.0 0.1+ 210311 W87 0.2- 0.2+ 210422 E85 0.8- 0.3+ 210215 807 0.0 0.1+ 210312 W94 0.0 0.0 210422 E85 0.2+ 0.1+ 210215 807 0.1- 0.1+ 210312 W94 0.2- 0.1+ 210422 E85 0.2+ 0.1+ 210215 807 0.1+ 0.0 210312 W94 0.3- 0.2+ 210422 E85 0.6+ 0.5- 210215 807 0.3+ 0.4- 210314 W85 0.4- 0.4+ 210423 X03 0.3- 0.6+ 210216 W88 0.3- 0.3- 210314 W85 0.2- 0.3+ 210423 X03 0.5+ 0.3- 210216 W88 0.1+ 0.2+ 210314 W85 0.2- 0.4+ 210423 X03 0.9- 0.9+ 210217 474 0.1+ 0.1- 210314 W85 0.1- 0.4+ 210423 X03 0.0 0.1- 210217 474 0.0 0.0 210318 T08 0.2+ 0.4- 210423 X03 0.2+ 1.8- 210217 474 0.6- 0.0 210318 T08 0.1+ 0.6- 210501 T08 0.5- 0.6+ 210217 Q62 0.2+ 0.4+ 210318 T08 0.5- 0.2+ 210501 T08 1.0+ 0.7+ 210217 Q62 0.5+ 0.5+ 210318 T08 0.5- 0.2- 210501 T08 0.4+ 0.6- 210218 E94 0.1- 0.0 210320 T05 0.5- 0.3- 210501 T08 0.3+ 0.5- 210218 E94 0.5+ 0.4- 210320 T05 0.3- 0.3- 210503 T05 0.9+ 0.8- 210218 E94 0.1- 1.1- 210320 T05 0.1- 0.8- 210503 T05 1.1+ 0.0 210218 E94 0.6- 0.8- 210320 T05 0.6+ 0.7- 210503 T05 1.1+ 1.4- 210218 Q62 1.4+ 0.5- 210322 T08 0.5- 0.7+ 210503 T05 0.3+ 0.1+ 210218 Q62 0.3- 0.3- 210322 T08 0.1- 1.1- 210509 T08 0.6+ 0.4+ 210218 Q62 1.3+ 0.0 210322 T08 0.3- 0.4- 210509 T08 (2.1+ 0.8-) 210220 Q62 0.1+ 0.1- 210322 T08 0.2+ 0.1- 210509 T08 0.3+ 0.0 210220 Q62 0.1- 0.1+ 210326 T08 0.5- 0.1- 210509 T08 0.2+ 0.4+ 210220 Q62 0.2+ 0.3+ 210326 T08 0.7+ 0.1- 210515 F51 0.5- 0.3+ 210220 474 0.0 0.2- 210326 T08 0.3- 0.1+ 210515 F51 0.5- 0.3+ 210220 474 0.2- 0.0 210326 T08 0.3+ 0.3+ 210515 F51 0.3- 0.3+ 210220 474 0.0 0.0 210403 T08 0.2- 0.2- 210515 F51 0.1- 0.2+ 210222 X02 0.6+ 0.4+ 210403 T08 0.6+ 0.3- 210517 T08 0.5+ 0.3+ 210222 X02 0.3- 0.6+ 210403 T08 0.6+ 0.1- 210517 T08 0.1+ 0.6- 210222 Q62 0.2- 0.4- 210403 T08 0.1- 0.2+ 210517 T08 (1.5+ 2.7-) 210222 Q62 0.2+ 0.2- 210407 T08 0.6+ 0.1- 210517 T08 0.1+ 0.2+ 210227 Q63 0.0 0.1+ 210407 T08 0.4+ 0.2- 210530 215 0.4+ 1.0- 210227 Q63 0.0 0.1+ 210407 T08 0.4+ 0.2- 210530 215 0.6+ 0.6- 210227 Q63 0.0 0.2+ 210407 T08 0.3+ 0.2- 210530 215 0.2+ 0.5- 210227 Q63 0.0 0.1+ 210411 E94 0.1+ 0.4+ 210531 T05 1.1+ 0.9- 210302 K93 0.1- 0.3+ 210411 E94 0.1- 0.8+ 210531 T05 0.0 0.4- 210302 K93 0.0 0.0 210411 E94 0.4+ 0.1- 210531 T05 (2.0+ 1.7-) 210302 K93 0.0 0.2+ 210411 E94 1.5+ 0.1- 210531 T05 0.9+ 0.7- 210302 K93 0.0 0.1+ 210417 T05 0.4+ 0.2- 210609 Q11 0.1+ 0.7- 210305 W85 0.4- 0.7+ 210417 T05 0.7+ 0.0 210609 Q11 0.3+ 1.0- 210305 W85 0.2+ 0.7+ 210417 T05 0.2+ 0.1+ 210609 Q11 0.1+ 1.0- ( ) -------- Rejected Obs.
Associate of the CBAT Syuichi Nakano 2021 June 24