Nakano Note (Nakano wa Kangaeru noda) NK 5548 C/2025 K4 (Siverd)
The following improved orbital elements, by S. Nakano, are from 29 observations 2025 May 30 to Sept. 18. 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. See an orbit in CBET 5565. Epoch = 2025 July 24.0 TT T = 2025 July 28.26518 +/- 0.00560 (m.e.) TT Peri. = 326.93520 +/- 0.00197 Node = 297.08281 +/- 0.00062 (2000.0) Inc. = 38.54368 +/- 0.00060 q = 2.5322050 +/- 0.0000334 AU e = 0.9415833 +/- 0.0000642 a = 43.35 AU P = 285.4 years 1/a = +0.0230695 +/- 0.0000253 1/AU origin = +0.023023 (Q= 6) future = +0.023060 The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 2025/ 250602 807 0.4- 0.0 250606 Y05 0.0 0.1- 250530 M22 0.3+ 0.2+ 250602 807 0.0 0.6+ 250606 Y05 0.1- 0.2- 250530 M22 0.8- 0.3- 250604 X09 0.3+ 0.8+ 250617 Q62 0.0 0.4+ 250530 M22 1.2+ 0.3+ 250604 X09 0.0 0.4- 250617 Q62 0.1- 0.1- 250530 M22 0.2- 0.0 250604 X09 0.1- 0.3- 250619 X03 (0.4- 7.5-) 250531 Q62 0.6+ 0.0 250605 I47 0.4- 1.4+ 250619 X03 (0.9+ 5.6-) 250531 Q62 0.1+ 0.1+ 250605 I47 0.4+ 0.8+ 250619 X03 (1.1+ 3.5-) 250531 M28 0.2+ 0.9- 250605 807 0.5- 0.3- 250815 Q62 0.2+ 0.2- 250531 M28 0.6+ 0.6- 250605 807 0.2- 0.1- 250815 Q62 0.1+ 0.2- 250531 M28 0.5+ 0.1- 250606 807 1.2- 0.9- 250918 Q62 0.1+ 0.0 250602 807 0.5- 0.2- 250606 Y05 0.1+ 0.1+ 250918 Q62 0.3- 0.2+ ( ) -------- Rejected Obs.
Associate of the CBAT Syuichi Nakano 2026 Feb. 11