Nakano Note (Nakano wa Kangaeru noda) NK 2409 280P/Larsen (2004 H2 = 2013 C1)
The following improved orbital elements, by S. Nakano, are from 82 observations 2004 to 2013. Perturbations by Mercury to Neptune and three minor planets, Ceres, Pallas and Vesta, were taken into account. The mean residual is +/- 0.67 arc second. RunOff values from the prediction in NK 1232 (= HICQ 2012) were +465" (R. A.) and -127" (Decl.) with delta-T correction = -0.55 day. Epoch = 2013 Dec. 14.0 TT T = 2013 Dec. 11.06246 +/- 0.02217 (m.e.) TT Peri. = 104.60317 +/- 0.00430 Node = 131.50799 +/- 0.00026 (2000.0) Inc. = 11.77237 +/- 0.00005 q = 2.6359441 +/- 0.0000189 AU e = 0.4175036 +/- 0.0000040 a = 4.5252540 +/- 0.0000099 AU n' = 0.10238578 +/- 0.00000033 P = 9.626 +/- 0.0000315 years T = 2004 May 10.97463 TT Epoch = 2004 Apr. 25.0 TT Peri. = 104.56305 e = 0.4187403 Node = 131.55296 (2000.0) a = 4.5024858 AU Inc. = 11.78625 n'= 0.10316338 q = 2.6171134 AU P = 9.554 years The predicted orbit for the 2023 return is as follows: T = 2023 Aug. 4.75206 TT Epoch = 2023 Aug. 4.0 TT Peri. = 104.74435 e = 0.4171291 Node = 131.38137 (2000.0) a = 4.5295464 AU Inc. = 11.77202 n'= 0.10224028 q = 2.6401407 AU P = 9.640 years The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 2004/ 040424 170 0.7- 0.2+ 040613 360 0.2+ 0.1- 040419 691 0.2+ 0.1+ 040424 170 0.2+ 0.9- 040613 360 0.8+ 0.0 040419 691 0.2- 0.7+ 040425 372 1.4- 1.9- 040621 246 1.1+ 0.1+ 040419 691 0.2+ 0.1- 040428 360 0.4- 0.0 040621 246 1.4+ 0.2- 040420 291 0.9+ 0.7+ 040428 360 1.0- 0.3+ 040621 246 1.7+ 0.0 040420 291 1.3+ 0.9- 040430 118 0.2- 0.4- 040622 691 0.4+ 0.1- 040420 291 0.9- 1.9- 040430 118 1.4+ 0.8+ 040622 691 0.0 0.3+ 040420 176 0.4- 0.6+ 040514 699 (2.2- 2.7+) 040622 691 0.3- 0.7+ 040420 176 0.2- 0.5+ 040514 699 1.0- 0.6- 040709 213 0.4- 0.2+ 040420 176 0.2+ 0.2+ 040514 699 0.6- 0.4- 040709 213 0.3- 0.2+ 040421 113 1.3- 0.6+ 040514 699 1.4- 0.2- 040709 213 0.7- 0.6+ 040421 113 1.0- 0.6+ 040514 360 0.1+ 0.2- 2013/ 040421 113 0.9- 0.8+ 040514 360 0.4- 0.2- 130205 291 0.1- 0.2- 040421 854 (2.5- 0.6+) 040514 360 0.1+ 0.9- 130205 291 0.0 0.2- 040421 854 0.2+ 0.4+ 040517 215 0.0 1.2- 130205 291 0.0 0.3- 040421 H36 1.6- 0.0 040522 703 0.1+ 0.5- 130206 291 0.1- 0.2- 040421 673 0.6+ 0.1+ 040522 703 0.7+ 0.6- 130206 291 0.2- 0.2- 040421 H36 0.1+ 0.1+ 040522 703 1.4- 1.4+ 130206 291 0.2- 0.4- 040421 673 0.7+ 0.3+ 040522 703 (3.3- 1.6+) 130207 H06 0.2+ 0.2- 040421 711 0.5+ 0.3+ 040524 704 0.3+ 0.1- 130207 H06 0.4- 0.2- 040421 673 0.9+ 0.3+ 040524 704 1.7+ 0.5- 130214 J04 0.1+ 0.2+ 040421 673 1.0+ 0.6+ 040524 704 0.4- 0.1- 130214 J04 0.3+ 0.5+ 040421 H36 0.4+ 0.4- 040524 704 0.3+ 0.0 130214 J04 0.5+ 0.1+ 040421 711 0.2+ 0.6+ 040524 704 0.3- 0.1+ 130214 J04 0.9+ 0.1+ 040421 673 0.6+ 0.8+ 040524 360 0.7+ 0.2- 130302 703 0.1+ 0.3- 040421 673 0.6+ 0.7+ 040524 360 0.0 0.3- 130302 703 0.7- 0.5+ 040423 360 0.2- 1.4- 040524 360 0.5+ 0.3- 130302 703 0.1- 1.6+ 040423 360 0.8- 1.1- 040605 170 0.5+ 0.9+ 130302 703 (0.3- 2.1+) 040423 360 1.9- 0.5- 040605 170 0.0 0.7+ 040424 170 0.8- 0.1+ 040613 360 0.4+ 0.5+ ( ) -------- Rejected Obs.
Associate of Central Bureau for Astronomical Telegrams Syuichi Nakano 2013 Mar. 5