OAA computing section circular NK 1781 Missing Comet returns in 2012
5D/Brorsen T = 2012 Feb. 5.29289 TT Epoch = 2012 Feb. 3.0 TT Peri. = 19.36227 e = 0.8325925 Node = 96.78752 (2000.0) a = 3.1575005 AU Inc. = 19.88193 n'= 0.17566650 q = 0.5285892 AU P = 5.611 years A1 = +1.323 A2 = +0.13425 From an orbit in NK 663 (= NK 946) [ 120 observations 1868-1879, mean residual 2".69 ]. D/1886 K1 (Brooks 1) T = 2012 Feb. 6.28499 TT Epoch = 2012 Feb. 3.0 TT Peri. = 208.61512 e = 0.4691281 Node = 39.19160 (2000.0) a = 3.5520339 AU Inc. = 10.93298 n'= 0.14722732 q = 1.8856750 AU P = 6.694 years From Buckley orbit (NK 858) [ 39 observations 1886 May 25-July 3 ]. 3D/Biela - A T = 2012 Feb. 27.02731 TT Epoch = 2012 Mar. 14.0 TT Peri. = 274.26435 e = 0.7711072 Node = 193.96503 (2000.0) a = 3.5144894 AU Inc. = 7.93653 n'= 0.14959281 q = 0.8044414 AU P = 6.589 years From an orbit in NK 851A [ 19 observations 1846-1852, mean residual 3".41 ]. D/1894 F1 (Denning) T = 2012 Apr. 16.79582 TT Epoch = 2012 Apr. 23.0 TT Peri. = 209.86045 e = 0.6643248 Node = 287.30097 (2000.0) a = 4.0382371 AU Inc. = 7.66992 n'= 0.12145526 q = 1.3555361 AU P = 8.115 years From Green orbit (HOAA 1995) [ 36 observations 1894 Mar. 27-June 5, mean residual 0".81 ]. 3D/Biela - B T = 2012 Oct. 9.86519 TT Epoch = 2012 Sept.30.0 TT Peri. = 272.62826 e = 0.7661616 Node = 195.56898 (2000.0) a = 3.5683214 AU Inc. = 7.48522 n'= 0.14622045 q = 0.8344104 AU P = 6.741 years A1 = +1.043 A2 = +0.03315 From an orbit in NK 851B [ 26 observations 1832-1852, mean residual 2".09 ].
Managing Director of the Oriental Astronomical Association Syuichi Nakano 2009 May 9