------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 1217 1997 Jul 27 13.37UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP,England.Telephone/FAX(01256)471074Int:+441256471074 INTERNET: GUY@TAHQ.DEMON.CO.UK GMH at AST.STAR.RL.AC.UK WORLD WIDE WEB http://www.demon.co.uk/astronomer ------------------------------------------------------------------- COMET C/1997 O1 (TILBROOK) A. Beresford informs us that he reported the name of the comet's discoverer incorrectly (cf. IAUC 6705): it should be Justin Tilbrook. There was also an error in the observed R.A.: for 12 28.4 read 12 18.4. IAUC 6707 Orbital elements by Brian Marsden: T 1997 July 16.5600 TT w 339.10400 ) e 1.00000000 O 231.32900 ) 2000.0 q 1.3855000 A.U. i 114.11500 ) Source: IAUC 6707 Positions are geocentric Ephemeris by G.Hurst using EPH.EXE by N.James: m = 8.0 + 5.0 log R + 10.0 log r Date R.A. (2000) Dec. R r Elong Mag. Motion h m o ' (AU) (AU) o "/hr P.A. 1997 July 27.00 12 28.70 -15 6.0 1.386 1.394 69.0 10.2 142 33 28.00 12 30.79 -14 19.3 1.408 1.396 68.1 10.2 138 33 29.00 12 32.84 -13 34.0 1.429 1.397 67.3 10.2 134 33 30.00 12 34.83 -12 50.2 1.451 1.399 66.4 10.3 130 34 31.00 12 36.77 -12 7.9 1.473 1.401 65.6 10.3 126 34 1997 Aug 1.00 12 38.67 -11 26.9 1.495 1.404 64.7 10.3 122 34 2.00 12 40.53 -10 47.2 1.517 1.406 63.9 10.4 119 35 3.00 12 42.35 -10 8.8 1.539 1.409 63.1 10.4 116 35 4.00 12 44.14 -9 31.5 1.561 1.411 62.3 10.5 113 35 5.00 12 45.88 -8 55.4 1.583 1.414 61.4 10.5 110 36 6.00 12 47.60 -8 20.5 1.605 1.417 60.6 10.5 107 36 7.00 12 49.29 -7 46.6 1.627 1.420 59.8 10.6 104 37 8.00 12 50.94 -7 13.7 1.650 1.424 59.0 10.6 102 37 9.00 12 52.57 -6 41.8 1.672 1.427 58.2 10.7 99 37 10.00 12 54.17 -6 10.8 1.694 1.431 57.4 10.7 97 38 11.00 12 55.75 -5 40.8 1.716 1.434 56.6 10.7 94 38 12.00 12 57.30 -5 11.6 1.737 1.438 55.8 10.8 92 39 13.00 12 58.84 -4 43.2 1.759 1.442 55.0 10.8 90 39 14.00 13 0.35 -4 15.6 1.781 1.446 54.3 10.9 88 39 15.00 13 1.84 -3 48.8 1.803 1.450 53.5 10.9 86 40 16.00 13 3.31 -3 22.7 1.824 1.455 52.7 10.9 85 40 17.00 13 4.76 -2 57.2 1.845 1.459 52.0 11.0 83 41 18.00 13 6.20 -2 32.5 1.867 1.464 51.2 11.0 81 41 19.00 13 7.62 -2 8.4 1.888 1.468 50.5 11.0 80 42 20.00 13 9.03 -1 44.9 1.909 1.473 49.7 11.1 78 42 V632 CYGNI A recent outburst of this recurrent object has been detected: 1997 July 8.192UT, 14.3 (D.York, USA); 8.260, 14.2 (G.Hanson, USA); 9.065, 14.2 (Gary Poyner, Birmingham, England). COMET HALE-BOPP HANDBOOK Further articles are needed and should now be sent as soon as possible to Nick James at: ndj@astro1.demon.co.uk to arrive by the end of this month at the latest. Guy M Hurst