Nakano Note (Nakano wa Kangaeru noda) NK 2168 97P/Metcalf-Brewington 1991A1
The following improved orbital elements, by S. Nakano, are from 150 observations 1991-2011, including planetary perturbations by Mercury to Neptune and three minor planets, Ceres, Pallas, Vesta, and non-gravitational effect of style II. The mean residual is +/- 0.84 arc second. The delta-T correction for the prediction in NK 1608 (= MPC 62881) was -0.046 day with RunOff values +46" for R. A. and -4" for Decl. on 2011 Sept. 3 observations. Epoch = 2011 Aug. 27.0 TT T = 2011 Aug. 20.95670 +/- 0.00170 (m.e.) TT Peri. = 228.21191 +/- 0.00037 Node = 185.20799 +/- 0.00006 (2000.0) Inc. = 17.88628 +/- 0.00005 q = 2.5966760 +/- 0.0000072 AU e = 0.4593234 +/- 0.0000020 a = 4.8026417 +/- 0.0000046 AU n' = 0.09364483 +/- 0.00000014 P = 10.525 +/- 0.0000153 years A1 = -1.170 +/- 0.566 A2 = -1.43345 +/- 0.04956 T = 1991 Jan. 5.62711 TT Epoch = 1991 Jan. 24.0 TT Peri. = 208.04852 e = 0.5939121 Node = 187.78839 (2000.0) a = 3.9190714 AU Inc. = 13.02837 n'= 0.12703673 q = 1.5914876 AU P = 7.758 years T = 2001 Apr. 15.00726 TT Epoch = 2001 Apr. 1.0 TT Peri. = 229.71560 e = 0.4564288 Node = 186.43868 (2000.0) a = 4.8033326 AU Inc. = 17.98524 n'= 0.09362462 q = 2.6109530 AU P = 10.527 years The predicted orbit for the 2022 return is as follows: T = 2022 Feb. 15.54461 TT Epoch = 2022 Mar. 2.0 TT Peri. = 229.96849 e = 0.4599192 Node = 184.07867 (2000.0) a = 4.7588384 AU Inc. = 17.95220 n'= 0.09494075 q = 2.5701571 AU P = 10.381 years The following residuals in seconds of arc are from the above orbital elements: Date Code Residual(") Date Code Residual(") Date Code Residual(") 1991/ 910202 046 1.7- 0.2+ 001002 704 0.1- 0.6+ 910105 412 (5.7+ 3.5-) 910202 056 (5.3+ 1.8-) 001002 704 0.5+ 0.4+ 910105 412 (0.5- 3.1-) 910203 056 (3.6+ 0.9-) 001002 704 0.5+ 0.8+ 910107 897 (5.3+ 0.2+) 910203 056 (5.0+ 0.6-) 001002 704 0.7- 0.8+ 910107 897 (4.4+ 1.1+) 910204 323 0.3+ 0.8- 001002 704 0.2+ 0.9+ 910108 413 0.5+ 0.9+ 910204 026 2.1- 1.3- 001005 402 0.9+ 0.7+ 910108 026 0.5+ 1.1+ 910205 323 2.4+ 0.9- 001005 402 0.2- 0.3- 910109 411 0.7- 0.8+ 910206 323 0.9+ 0.6- 001005 402 0.1+ 0.6- 910109 411 0.1+ 0.3+ 910207 323 1.6+ 0.1- 001029 704 0.7+ 1.9+ 910109 413 0.9+ 1.2+ 910208 323 1.0+ 0.9+ 001029 704 0.2+ 0.4- 910109 413 0.4- 0.0 910209 801 0.1+ 0.9+ 001029 704 0.8- 1.1- 910109 372 0.2- 0.3+ 910211 801 0.9+ 0.6+ 001029 704 0.1- 1.7- 910109 372 0.3- 1.4+ 910216 801 0.4+ 0.6- 001103 360 0.5+ 0.8- 910109 323 1.0+ 0.4- 910217 046 0.2- 1.0- 001103 360 0.6+ 0.3+ 910109 026 1.0- 1.2- 910217 046 1.1- 0.3+ 001118 699 0.2- 0.2+ 910110 897 0.2+ 0.4- 910218 046 0.4- 1.1- 001118 699 1.7+ 0.3+ 910110 897 2.1+ 0.4- 910218 046 1.3+ 0.1+ 001118 699 0.8+ 1.4- 910110 401 0.0 0.3- 910302 984 (1.0+ 3.5-) 001118 699 0.7- 0.3- 910110 401 0.6- 0.6- 910303 897 1.9+ 0.0 001119 699 1.1+ 0.7+ 910110 323 0.2+ 0.0 910303 897 (1.4+ 6.0+) 001119 699 1.1+ 0.6- 910110 503 0.5+ 0.8+ 910403 372 (3.0- 0.3-) 001119 699 0.6+ 1.2+ 910111 415 0.2- 0.9+ 910403 372 0.0 1.1- 001119 699 0.9+ 0.3- 910111 415 0.4- 1.2+ 2000/ 001122 360 0.3+ 0.1- 910111 323 1.2+ 0.9- 000901 704 0.0 0.4+ 001122 360 0.1- 0.4+ 910112 372 0.3- 2.3+ 000901 704 0.4- 0.7+ 001129 322 (3.2+ 1.8-) 910112 474 (2.5- 1.7+) 000901 704 0.2+ 0.8- 001129 322 (4.8+ 1.0-) 910112 474 1.5- 2.3+ 000901 704 0.5- 0.4+ 001129 322 (0.1- 2.6-) 910113 372 0.4- 0.6+ 000902 699 (2.8- 0.6-) 001215 402 1.5+ 1.0- 910113 984 0.2+ 0.4+ 000902 699 0.9- 0.7- 001215 402 (2.1+ 0.3-) 910113 801 0.6+ 0.2+ 000902 699 1.4- 0.2- 001215 402 (2.4+ 1.1+) 910113 801 0.4+ 0.3+ 000902 699 0.5- 0.6- 001222 360 0.4+ 0.0 910113 801 0.4+ 0.2+ 000903 704 0.8- 1.6+ 001222 360 0.5+ 0.2- 910114 503 0.1+ 0.0 000903 704 0.2+ 0.5+ 001223 704 0.1+ 0.6+ 910115 897 0.6+ 0.2- 000905 704 0.6+ 1.0+ 001223 704 0.8+ 0.5+ 910115 372 0.2+ 0.0 000905 704 0.3+ 1.4+ 001223 704 0.3- 0.9- 910115 364 0.4- 0.8- 000905 704 0.6+ 1.2+ 2011/ 910115 364 0.6- 0.0 000905 704 0.1- 1.4+ 110903 C10 0.5+ 0.3- 910115 875 1.1- 0.4+ 000909 540 0.3- 0.4- 110903 C10 0.2- 1.1- 910115 875 2.3- 0.0 000909 540 1.3- 0.4+ 110903 C10 0.1+ 0.5- 910117 474 1.5- 1.4+ 000909 540 0.3- 0.4+ 110905 C10 0.7+ 1.4- 910117 474 1.9- 0.4+ 000924 704 0.1- 0.1- 110905 C10 1.5+ 0.7- 910117 364 0.3- 2.3- 000924 691 1.2- 0.8- 111003 C32 0.2- 0.1+ 910117 364 0.3+ 0.9- 000924 704 0.6- 0.2- 111004 C32 0.2- 0.1+ 910117 984 1.8- 0.7- 000924 704 1.5- 0.4- 111004 C32 0.3+ 0.4- 910117 801 0.3+ 1.0- 000924 691 0.6- 0.6- 111009 C32 0.1+ 0.6- 910118 026 1.3+ 0.4- 000924 704 0.5- 1.2- 111009 C32 1.2+ 0.0 910119 897 1.0- 0.8- 000924 691 0.3- 0.9+ 111022 C32 0.8+ 0.6- 910119 897 0.5- 1.2+ 000926 704 0.3+ 0.5- 111022 C32 0.1+ 0.8+ 910119 897 2.3+ 0.1- 000926 704 0.4+ 0.1+ 111022 C32 0.4- 1.5+ 910120 657 0.1- 0.3+ 000926 704 0.1- 0.4- 111022 C32 0.6- 0.7+ 910122 364 0.4- 1.4+ 000926 704 0.2+ 0.6- 111024 C10 0.3+ 0.5+ 910122 364 1.1+ 0.0 000926 704 0.0 0.8- 111024 C10 (3.2- 2.0+) 910125 046 1.5- 1.0- 000926 360 0.0 0.1- 111030 H06 0.4+ 1.0+ 910125 046 (2.9- 0.6+) 000926 360 0.5- 0.4+ 111030 H06 0.5+ 0.1- 910201 046 0.8+ 0.8- 000926 360 0.3- 0.3- 111104 C32 (2.1- 0.6-) 910201 046 1.2+ 0.3+ 001001 704 0.3+ 0.6+ 111104 C32 1.0- 0.8+ 910202 056 (3.9+ 0.1-) 001001 704 0.0 0.1+ 111120 C10 1.4- 0.3+ 910202 046 2.2- 1.0- 001001 704 1.1- 0.4- 111120 C10 1.6- 0.2+ ( ) -------- Rejected Obs.
Associate of Central Bureau for Astronomical Telegrams Syuichi Nakano 2011 Nov. 26