OAA computing section circular NK 611 26P/Grigg-Skjellerup
The following improved orbital elements, by K. Muraoka, are from 173 observations 1961-1992, including planetary perturbations by Mercury to Pluto and five minor planets and non-gravitational effect of style II. The mean residual is +/- 0.93 arc second. T = 1992 July 22.13793 TT Epoch = 1992 Aug. 6.0 TT Peri. = 359.26520 e = 0.6643256 Node = 213.34030 (2000.0) a = 2.9632569 AU Inc. = 21.09897 n'= 0.19321913 q = 0.9946895 AU P = 5.101 years A1 = -0.002 A2 = -0.00113 T = 1961 Dec. 31.35760 TT Epoch = 1962 Jan. 16.0 TT Peri. = 356.36930 e = 0.7029771 Node = 216.07453 (2000.0) a = 2.8878605 AU Inc. = 17.61507 n'= 0.20083516 q = 0.8577607 AU P = 4.908 years T = 1967 Jan. 16.47515 TT Epoch = 1967 Jan. 30.0 TT Peri. = 359.15954 e = 0.6624355 Node = 213.39429 (2000.0) a = 2.9711461 AU Inc. = 21.04405 n'= 0.19245006 q = 1.0029536 AU P = 5.121 years T = 1972 Mar. 2.65281 TT Epoch = 1972 Feb. 13.0 TT Peri. = 359.27087 e = 0.6628377 Node = 213.36061 (2000.0) a = 2.9698091 AU Inc. = 21.06199 n'= 0.19258004 q = 1.0013078 AU P = 5.118 years T = 1977 Apr. 11.00068 TT Epoch = 1977 Apr. 7.0 TT Peri. = 359.31083 e = 0.6647057 Node = 213.35368 (2000.0) a = 2.9627272 AU Inc. = 21.09842 n'= 0.19327095 q = 0.9933857 AU P = 5.100 years T = 1982 May 14.99670 TT Epoch = 1982 May 31.0 TT Peri. = 359.31691 e = 0.6656803 Node = 213.34125 (2000.0) a = 2.9589857 AU Inc. = 21.13128 n'= 0.19363764 q = 0.9892473 AU P = 5.090 years T = 1987 June 18.04614 TT Epoch = 1987 June 14.0 TT Peri. = 359.30578 e = 0.6647128 Node = 213.33550 (2000.0) a = 2.9625439 AU Inc. = 21.10052 n'= 0.19328888 q = 0.9933030 AU P = 5.099 years The predicted orbit for the 1997 return (MPC 23483) is as follows: T = 1997 Aug. 30.30353 TT Epoch = 1997 Aug. 20.0 TT Peri. = 359.33182 e = 0.6638058 Node = 213.30916 (2000.0) a = 2.9649842 AU Inc. = 21.08677 n'= 0.19305030 q = 0.9968104 AU P = 5.105 years
Director, Computing Section Syuichi Nakano 1994 Apr. 21