OAA computing section circular NK 513 Periodic Comet Shoemaker 2 1984 XVIII
The following improved orbital elements, by S. Nakano, are from eight observations 1984 Nov. 18 to Dec. 20. Perturbations by all nine planets were taken into account. The mean residual is +/- 1.27 arc seconds: Epoch = 1984 Sept.17.0 ET T = 1984 Sept.26.69047 +/- 0.00909 (m.e.) ET Peri. = 317.56927 +/- 0.02187 Node = 54.81887 +/- 0.02182 (1950.0) Inc. = 21.56439 +/- 0.00771 q = 1.3196979 +/- 0.0030504 AU e = 0.6656651 +/- 0.0005346 a = 3.9472336 +/- 0.0065879 AU n_ = 0.12567961 +/- 0.00031464 P = 7.842 +/- 0.0196330 years (+/- 7.17 days) The predicted orbit for the 1992 return is as follows: T = 1992 Aug. 6.87542 ET Epoch = 1992 Aug. 6.0 ET Peri. = 317.62673 e = 0.6646408 Node = 54.74889 (1950.0) a = 3.9572459 AU Inc. = 21.54886 n_= 0.12520294 q = 1.3270989 AU P = 7.872 years The following residuals in seconds of arc are from the above orbital elements: Date/ UT R.A. (1950) Decl. *** O-C *** Code/Obs h m s ! , " " " 1984 11 18.25347 03 09 18.39 +16 07 14.8 1.6+ 0.7- 688/LO 1984 11 18.30625 03 09 13.90 +16 09 32.8 1.8- 1.1- 688/LO 1984 11 21.32708 03 05 39.47 +18 16 51.2 ( 1.0+ 4.6+) 675/PL 1984 11 21.34444 03 05 38.12 +18 17 31.5 0.1+ 2.8+ 675/PL 1984 11 27.20278 02 59 45.31 +21 56 39.7 ( 0.0 5.4+) 688/LO 1984 11 27.24861 02 59 42.86 +21 58 03.1 ( 3.1+ 5.8-) 688/LO 1984 11 28.68056 02 58 30.3 +22 46 11 1.5+ 1.0+ 372/sk Y 1984 11 30.35880 02 57 13.92 +23 39 48.4 0.3+ 1.9- 675/PL 1984 11 30.37616 02 57 12.94 +23 40 21.9 1.8- 0.4- 675/PL 1984 12 18.07989 02 52 38.46 +30 39 12.4 0.1- 0.2+ 801/HO 1984 12 20.27708 02 53 09.26 +31 16 10.8 0.2+ 0.2+ 707/ev ( ) -------- Rejected Obs.
Director, Computing Section Syuichi Nakano 1987 August 20