OAA computing section circular NK 1595 198P/ODAS (1998 X1 = 2006 B7); [Temporary numbered]
The following improved orbital elements, by S. Nakano, are from 183 observations 1998 to 2006, including planetary perturbations by Mercury to Neptune and three minor planets, Ceres, Pallas, Vesta, and using sublimating molecule = CO (or N2) from Yabushita's theory ( MN 283, 347). Former Water-Ice vaporization gives A1 = +15.81, A2 = -0.3861 and A3 = -2.07. Orbit will be changed to q= 3.341 AU, e= 0.232, Peri.= 189.3, Node= 240.7, Inc.= 8.7 since the approach to Jupiter ( 0.15 AU) on 2042 Sept. 27 UT. The mean residual is +/- 0.56 arc second. See a prediction in NK 844. Following observations were included: 12C103 C1999 02 12.18392 09 31 58.68 +16 02 51.9 17.8 Rc 699 12C103 C1999 02 12.20944 09 31 57.33 +16 02 56.7 c 699 12C103 C1999 02 12.23499 09 31 55.97 +16 03 02.2 c 699 Epoch = 2005 Apr. 20.0 TT T = 2005 May 3.11104 +/- 0.02229 (m.e.) TT Peri. = 68.95751 +/- 0.00426 Node = 358.81521 +/- 0.00121 (2000.0) Inc. = 1.34834 +/- 0.00004 q = 1.9812179 +/- 0.0000235 AU e = 0.4469265 +/- 0.0000162 a = 3.5821968 +/- 0.0000315 AU n' = 0.14537172 +/- 0.00000192 P = 6.780 +/- 0.0000895 years Y1 = +3.866 +/- 0.648 Y2 = +0.10360 +/- 0.04179 Y3 = -1.72057 +/- 0.03311 T = 1998 July 20.96522 TT Epoch = 1998 July 6.0 TT Peri. = 68.68138 e = 0.4478466 Node = 358.97520 (2000.0) a = 3.5761911 AU Inc. = 1.35162 n'= 0.14573806 q = 1.9746062 AU P = 6.763 years The predicted orbit for the 2012 return is as follows: T = 2012 Feb. 15.26881 TT Epoch = 2012 Feb. 3.0 TT Peri. = 68.91217 e = 0.4445887 Node = 358.61912 (2000.0) a = 3.5955215 AU Inc. = 1.34146 n'= 0.14456436 q = 1.9969933 AU P = 6.818 years The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 1998/ 981221 372 (2.6+ 0.4+) 990213 691 0.7- 0.6+ 981215 910 0.3+ 0.4- 981221 360 0.9+ 0.7+ 990213 691 0.5- 0.4- 981215 910 0.1- 0.9- 981221 360 0.6+ 0.1+ 990213 691 0.8- 0.9+ 981215 910 0.5+ 0.8- 981221 360 0.0 0.4+ 990213 691 0.4- 0.1- 981216 046 0.5- 0.3+ 981222 958 0.6+ 0.8+ 990213 691 0.5+ 0.8+ 981216 046 0.7- 0.6- 981222 958 0.7- 0.4+ 990214 693 0.1+ 0.1- 981216 046 0.5+ 1.0- 981222 958 0.4+ 0.0 990214 693 0.2+ 0.2- 981216 557 0.5- 0.5- 981224 360 0.1- 0.0 990214 693 0.1+ 0.2- 981216 910 0.5+ 0.3- 981224 360 0.4- 0.5+ 990214 360 0.2+ 0.4- 981216 046 0.5- 1.2- 981224 360 0.5+ 0.0 990214 360 0.3+ 0.2- 981216 046 1.0- 1.5- 981226 910 0.0 0.4- 990214 360 0.1+ 0.6- 981216 910 0.3+ 0.2- 981227 958 (0.0 3.9+) 990215 118 0.2+ 0.2- 981216 910 0.0 0.4- 981227 958 1.9- 0.5+ 990215 118 0.2- 0.3+ 981216 910 0.1- 0.6- 981227 402 0.4+ 0.1- 990216 691 0.7- 0.4- 981216 910 0.4- 1.2- 981227 402 0.2+ 0.5- 990216 691 0.2- 0.1+ 981216 586 0.7+ 0.2+ 981227 402 0.7+ 0.0 990216 691 1.1- 0.1- 981216 910 0.0 0.7- 1999/ 990216 615 0.5+ 0.6+ 981216 586 0.6+ 0.5+ 990107 897 1.6- 1.6+ 990216 615 0.8+ 0.2- 981216 586 0.7+ 0.2+ 990107 897 0.1+ 1.3+ 990216 615 0.1- 0.2+ 981216 586 0.8+ 0.5+ 990107 897 0.4- 1.5+ 990216 615 0.4+ 0.3+ 981216 586 0.6+ 0.3+ 990110 372 0.5- 1.2+ 990216 615 0.1- 0.2+ 981216 586 0.4+ 0.2+ 990113 693 0.7- 0.1- 990216 615 0.2- 0.0 981216 586 0.3+ 0.4+ 990113 693 0.7- 0.1- 990216 615 0.3- 0.2+ 981216 586 0.4+ 0.4+ 990113 693 0.6- 0.1- 990216 615 0.8- 0.8+ 981216 586 0.8+ 0.4+ 990114 910 0.8+ 0.1- 990216 615 0.2+ 0.2+ 981216 586 0.7+ 0.3+ 990114 910 0.8+ 0.6- 990216 615 0.1+ 0.6+ 981216 586 0.5+ 0.4+ 990114 910 0.6- 0.9- 990216 615 0.0 0.6+ 981216 586 0.6+ 0.5+ 990115 910 0.0 0.9- 990216 615 0.6- 0.4+ 981216 586 0.6+ 0.5+ 990115 910 0.5+ 0.8- 990216 615 0.2- 0.3+ 981216 611 0.2+ 0.8- 990115 910 0.6+ 1.4- 990216 615 0.2- 0.2+ 981217 611 (2.6- 0.8-) 990115 910 0.2- 1.5- 990216 615 0.3+ 0.6+ 981217 586 0.5- 0.2+ 990115 910 0.1+ 1.4- 990223 897 (1.5+ 2.7+) 981217 586 0.2+ 0.2+ 990115 910 0.3- 0.6- 990223 897 (3.5+ 0.0 ) 981217 046 0.9- 0.4- 990115 910 0.3- 1.1- 990223 897 0.8+ 0.8- 981217 586 0.1- 0.1- 990119 910 0.0 0.4+ 990316 402 0.9+ 0.4+ 981217 046 0.8- 0.3+ 990119 910 0.2+ 0.2+ 990316 402 (0.8+ 2.3-) 981217 046 0.4+ 0.1- 990119 910 0.2+ 0.1- 990316 402 0.7- 1.1- 981217 586 0.0 0.2+ 990119 910 0.6- 0.0 990404 402 0.1- 0.1+ 981217 046 0.2+ 0.0 990119 910 0.1- 0.2+ 990404 402 1.6+ 0.2- 981217 046 0.7+ 0.1- 990119 910 0.2- 0.2+ 990414 693 0.4- 0.6- 981217 586 0.4- 0.1+ 990119 910 0.3- 0.1+ 990414 693 (3.2- 0.7+) 981217 586 0.2- 0.2+ 990119 910 0.1- 0.2+ 2006/ 981217 586 0.5- 0.3+ 990119 910 0.0 0.0 060130 691 0.1- 0.6- 981217 586 0.3- 0.2+ 990119 910 0.2- 0.5+ 060130 691 0.4- 0.8- 981217 586 0.4- 0.3+ 990121 360 0.4+ 0.6- 060130 691 0.4- 0.9- 981217 586 0.6- 0.1+ 990121 360 0.3+ 0.2- 060207 691 0.3- 0.3- 981217 586 0.1- 0.3+ 990121 360 0.0 0.4- 060207 691 0.3- 0.5- 981217 586 0.1+ 0.1+ 990126 402 (2.1+ 0.8+) 060207 691 0.1+ 0.4- 981218 511 0.2+ 0.5+ 990126 360 0.1+ 0.1+ 060220 691 0.1+ 0.2- 981218 511 0.1+ 0.5+ 990126 360 0.4- 0.2- 060220 691 0.1- 0.2- 981218 511 0.0 0.3+ 990126 360 0.2+ 0.2- 060220 691 0.1- 0.1+ 981218 511 0.1- 0.4+ 990205 897 0.5+ 0.1+ 060224 691 0.1+ 0.3+ 981218 511 0.1- 0.4+ 990205 897 0.7- 1.1- 060224 691 0.1+ 0.0 981218 511 0.1+ 0.4+ 990206 402 0.1+ 0.7- 060224 691 0.4+ 1.0- 981218 511 0.0 0.4+ 990206 402 0.7+ 0.2- 060302 691 0.6- 0.1+ 981218 511 0.1- 0.6+ 990206 402 1.1+ 0.6+ 060302 691 0.2+ 0.5+ 981218 511 0.1- 0.7- 990208 402 1.3+ 0.6- 060302 691 0.1+ 0.4+ 981218 402 0.8- 0.5+ 990208 402 1.3+ 0.2- 060323 G96 0.9- 0.4+ 981218 402 0.5- 0.2+ 990208 402 1.2+ 0.6- 060323 G96 0.6+ 0.4+ 981218 402 0.3+ 0.1+ 990212 699 0.7- 1.0+ 060323 G96 0.9- 0.6+ 981218 402 0.4- 0.6+ 990212 699 0.4- 0.2+ 060323 G96 0.6+ 0.6+ 981219 897 0.8- 1.7- 990212 699 0.2- 0.1+ 060324 G96 0.3+ 0.3+ 981219 897 (3.1- 1.8-) 990213 691 0.5- 0.0 060324 G96 1.4+ 0.2+ 981219 372 (1.1+ 2.1+) 990213 691 0.7- 0.1- 060324 G96 0.2- 0.3+ 981219 372 0.8+ 1.7+ 990213 691 0.1+ 0.2+ 060324 G96 0.2+ 0.5+ 981220 897 (3.6- 0.2-) 990213 691 0.3- 0.1- ( ) -------- Rejected Obs.
Director, Computing Section Syuichi Nakano 2008 Apr. 1