OAA computing section circular NK 486 Periodic Comet Borrelly 1960 V = 1967 VIII = 1974 VII
= 1981 IV The following improved orbital elements, by S. Nakano, are from 45 observations 1960 to 1981, including full planetary per- turbations and non-gravitational effect of style II. The mean residual is +/- 1.54 arc seconds. Epoch = 1981 Feb. 5.0 ET T = 1981 Feb. 20.01046 +/- 0.00040 (m.e.) ET Peri. = 352.77093 +/- 0.00034 Node = 75.05882 +/- 0.00034 (1950.0) Inc. = 30.20092 +/- 0.00014 q = 1.3192728 +/- 0.0000023 AU e = 0.6314881 +/- 0.0000006 a = 3.5800001 +/- 0.0000028 AU nß = 0.14550553 +/- 0.000000003 P = 6.774 +/- 0.0000079 years A1 = +0.117 +/- 0.018 A2 = -0.03921 +/- 0.00095 T = 1960 June 13.23503 ET Epoch = 1960 May 26.0 ET Peri. = 350.97523 e = 0.6033783 Node = 76.19353 (1950.0) a = 3.6663690 AU Inc. = 31.06663 nß= 0.14039441 q = 1.4541614 AU P = 7.020 years T = 1967 June 17.71566 ET Epoch = 1967 May 30.0 ET Peri. = 351.02986 e = 0.6044478 Node = 76.14122 (1950.0) a = 3.6572715 AU Inc. = 31.11564 nß= 0.14091859 q = 1.4466417 AU P = 6.994 years T = 1974 May 12.65462 ET Epoch = 1974 Apr. 23.0 ET Peri. = 352.67326 e = 0.6319317 Node = 75.11867 (1950.0) a = 3.5768054 AU Inc. = 30.21577 nß= 0.14570052 q = 1.3165085 AU P = 6.765 years The predicted orbit for the 1987 return is as follows: T = 1987 Dec. 18.32565 ET Epoch = 1987 Dec. 31.0 ET Peri. = 353.32470 e = 0.6242163 Node = 74.74595 (1950.0) a = 3.6105400 AU Inc. = 30.32441 nß= 0.14366330 q = 1.3567822 AU P = 6.861 years The following residuals in seconds of arc (or two decimals in degrees) are from the above orbital elements: Date/ UT R.A. (1950) Decl. *** O-C *** Code/Obs. h m s ¡ , " " " 1960 09 25.49403 10 22 33.60 +29 22 12.2 1.3- 0.4+ 689/FS 1960 09 25.50234 10 22 34.90 +29 22 10.2 2.2- 0.3+ 689/FS 1960 10 25.48732 11 38 01.82 +27 14 31.6 1.2+ 0.1+ 689/FS 1960 10 25.50947 11 38 04.86 +27 14 26.7 1.4+ 0.2+ 689/FS 1960 12 18.45788 13 17 14.31 +26 25 19.3 1.8+ 0.4+ 689/FS - continued - NK 486 - 2 Date/ UT R.A. (1950) Decl. *** O-C *** Code/Obs. h m s ¡ , " " " 1960 12 19.45103 13 18 34.30 +26 28 34.9 1.2+ 0.3+ 689/FS 1961 01 13.49273 13 44 48.76 +28 49 45.0 1.6- 2.8- 689/FS 1961 02 22.39316 13 49 53.52 +35 21 39.4 0.7- 0.7- 689/FS 1967 10 05.58257 10 45 02.32 +28 45 43.2 ( 0.14+ 0.02-) 371/tm 1967 10 05.58328 10 45 03.61 +28 45 39.9 ( 0.14+ 0.02-) 371/tm 1967 10 07.83109 10 50 19.22 +28 37 24.6 1.2+ 1.4+ 371/tm 1967 10 08.82693 10 52 54.56 +28 33 15.5 0.5- 1.1+ 371/tm 1967 12 08.81979 13 01 00.19 +26 14 56.7 ( 0.4- 6.2-) 387/tm 1968 01 30.77164 13 52 35.95 +31 39 10.2 2.8- 0.9+ 371/tm 1973 08 23.06809 20 47 00.43 -55 26 07.4 0.9+ 1.8+ 821/AL 1973 08 23.09726 20 46 58.01 -55 26 14.1 2.3+ 0.6+ 821/AL 1974 11 10.40640 12 56 32.32 +20 11 54.2 3.8+ 2.4+ 801/HO 1974 12 23.40516 13 58 56.65 +18 12 55.9 1.2+ 0.4+ 801/HO 1975 01 23.79653 14 25 28.21 +19 48 36.1 (11.0- 4.0+) 372/sk 1975 01 23.81528 14 25 28.86 +19 48 41.1 ( 9.8- 2.7+) 372/sk 1975 03 05.34826 14 25 43.92 +24 49 03.0 2.3- 1.7+ 801/HO 1975 03 19.25156 14 16 04.98 +26 30 16.9 1.3- 0.8+ 801/HO 1980 07 09.31181 23 43.96 -43 32.6 (11.7- 35.4-) 809/ES Y 1980 07 09.32570 23 43 57.12 -43 31 47.2 (23.4- 25.1+) 809/ES 1980 07 21.34514 23 51 17.71 -46 31 02.2 0.1+ 1.8+ 809/ES 1980 07 21.36875 23 51 18.31 -46 31 25.1 0.3+ 1.4+ 809/ES 1980 09 09.76919 23 25 38.00 -58 47 22.3 0.9+ 0.7+ 323/PR 1980 10 29.57187 22 36 19.64 -53 20 25.8 0.5- 0.8- 323/PR 1980 11 07.54236 22 39 55.35 -50 21 16.1 0.5+ 0.5+ 323/PR 1980 11 26.51319 22 58 35.92 -42 39 26.2 ( 1.0+ 5.1+) 323/PR 1980 12 02.05278 23 06 13.40 -40 05 15.5 2.2- 1.3- 809/ES 1980 12 02.08056 23 06 15.92 -40 04 26.0 0.2- 0.1+ 809/ES 1980 12 05.47352 23 11 19.86 -38 25 42.2 3.0+ 0.6- 474/JN 1980 12 05.48490 23 11 20.79 -38 25 22.7 1.7+ 1.4- 474/JN 1980 12 12.56875 23 22 44.31 -34 49 18.4 ( 4.8- 2.5+) 323/PR 1980 12 14.16391 23 25 27.01 -33 58 58.5 2.9- 1.2+ 675/PL 1980 12 30.40949 23 55 24.43 -24 49 54.2 1.7- 2.1- 386/YT 1980 12 30.41719 23 55 25.32 -24 49 38.3 1.7- 2.8- 386/YT 1981 01 03.41574 00 03 22.4 -22 25 19 1.3- 2.0+ 386/YT Y 1981 01 04.42031 00 05 24.35 -21 48 36.9 1.1+ 0.2- 386/YT 1981 01 26.12050 00 52 08.71 -07 58 17.1 1.1- 1.5- 675/PL 1981 01 27.10644 00 54 23.78 -07 19 26.5 0.6- 0.1+ 675/PL 1981 01 28.79170 00 58 16.13 -06 13 01.1 0.8- 0.2- 491/CN 1981 01 29.80214 01 00 36.37 -05 33 09.3 1.0- 0.8- 491/CN 1981 01 30.41701 01 02 02.21 -05 08 48.2 1.0+ 3.4+ 375/ei 1981 01 30.43438 01 02 04.59 -05 08 11.6 0.7+ 1.1- 375/ei 1981 01 30.98852 01 03 21.92 -04 46 18.0 2.4- 0.3+ 801/HO 1981 02 05.43264 01 16 15.34 -01 11 30.6 ( 0.4- 5.6-) 375/ei 1981 02 05.43628 01 16 15.95 -01 11 18.7 0.9+ 2.3- 375/ei 1981 03 08.15208 02 36 48.1 +17 58 39 ( 1.5+ 4.6+) 657/VC 1981 03 09.14653 02 39 40.70 +18 32 24.9 ( 8.3+ 2.0+) 657/VC 1981 03 18.17222 03 06 34.88 +23 24 42.9 ( 8.8+ 3.2+) 657/VC 1981 03 30.46528 03 45 50.37 +29 14 21.6 2.2+ 2.6+ 394/tk 1981 03 30.47222 03 45 51.46 +29 14 30.4 1.7- 0.6+ 394/tk 1981 04 02.15868 03 54 51.43 +30 22 37.6 2.2+ 2.8+ 687/NA 1981 04 25.15556 05 17 12.01 +37 48 24.3 0.1- 2.3+ 687/NA 1981 05 12.18300 06 21 49.90 +40 33 17.4 0.9- 0.8- 675/PL 1981 05 13.18266 06 25 38.05 +40 38 43.6 0.2- 0.7- 675/PL ( ) -------- Rejected Obs.
Director, Computing Section Syuichi Nakano 1985 December 22