THE ASTRONOMER Electronic Circular No 671 1992 Sept 28 19.36UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke,
Hants, RG22 4PP,England. Telephone/FAX(0256)471074 Int:+44256471074
TELEX: 9312111261 Answerback: TA G TELECOM GOLD: 10074:MIK2885
GMH at UK.AC.RUTHERFORD.STARLINK.ASTROPHYSICS STARLINK: RLSAC::GMH
GMH at UK.AC.CAM.ASTRONOMY.STARLINK STARLINK: CAVAD::GMH
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PERIODIC COMET SWIFT-TUTTLE (1737 II = 1862 III = 1992t)
A message from H. Kosai, National Astronomical Observatory, Tokyo,
reports the discovery of a comet by Tsuruhiko Kiuchi, with the
suggestion that it might be P/Swift-Tuttle with perihelion time in
mid-December. Confirmation of the discovery by several observers
in Canada, the U.S. and Japan leaves no doubt that this
identification with the Perseid parent comet is correct. The
identification in turn confirms the suggestion (Lynn 1902, Obs. 25,
304; Marsden 1973, A.J.78, 662; see also IAUC 5330 and 5586) that
Kegler's 1737 observations were indeed of P/Swift-Tuttle.
1992 UT R.A. (2000) Decl. m1 Observer
Sept.26.75694 11 47.5 +59 00 11.5 Kiuchi
27.22465 11 50 34.71 +59 04 35.3 Tatum
T. Kiuchi (Usuda, Nagano). 25 x 150 binoculars. Comet diffuse
without condensation, diameter 4'.
J. B. Tatum (University of Victoria). 0.25-m Schmidt.
Precise linkage of the observations, even at two apparitions, is
not possible without the involvement of large nongravitational
forces. The following orbital elements, by Brian Marsden are a
compromise that fit the current observations exactly but leave
large discordances in 1862:
Epoch = 1992 Dec. 4.0 TT
T = 1992 Dec. 12.391 TT Peri. = 152.979
e = 0.96362 Node = 139.430 2000.0
q = 0.95876 AU Incl. = 113.408
a = 26.35441 AU n = 0.007285 P = 135.29 years
Total visual magnitude estimates: Sept. 27.41 UT, 9.1 (D. Machholz,
Colfax, CA, 29 x 127 binoculars; 4' coma); 27.47, 9.1 (C. S.Morris,
Pine Mountain Club, CA, 0.260m reflector; diffuse and uncondensed,
coma 5'.2); 27.48, 10.2 (A. Hale, Las Cruces, NM, 0.20-m reflector)
Ephemeris from the orbital elements on IAUC 5620:
1992 TT R. A. (2000) Decl. Delta r Elong. Phase m1
Sept.25 11 37.16 +58 52.3 1.837 1.595 60.1 33.0 9.3
27 11 49.18 +59 03.5 1.791 1.571 61.0 33.9 9.2
29 12 01.95 +59 12.2 1.744 1.548 61.8 34.8 9.1
Oct. 1 12 15.47 +59 17.8 1.699 1.524 62.6 35.7 9.0
3 12 29.78 +59 19.6 1.654 1.501 63.4 36.6 8.9
5 12 44.86 +59 16.7 1.610 1.478 64.1 37.5 8.7
7 13 00.69 +59 08.2 1.567 1.455 64.7 38.4 8.6
9 13 17.22 +58 53.0 1.525 1.432 65.3 39.3 8.5
11 13 34.37 +58 30.2 1.484 1.409 65.8 40.3 8.3
13 13 52.05 +57 58.7 1.445 1.386 66.3 41.2 8.2
15 14 10.11 +57 17.5 1.407 1.364 66.6 42.1 8.1
17 14 28.39 +56 25.5 1.372 1.342 66.9 43.1 8.0
19 14 46.72 +55 22.1 1.338 1.320 67.0 44.0 7.8
21 15 04.94 +54 06.5 1.307 1.299 67.1 44.9 7.7
23 15 22.86 +52 38.6 1.278 1.277 67.0 45.8 7.6
25 15 40.35 +50 58.2 1.253 1.256 66.9 46.7 7.5
27 15 57.26 +49 05.6 1.230 1.236 66.6 47.5 7.4
29 16 13.49 +47 01.3 1.210 1.216 66.1 48.3 7.3
31 16 28.98 +44 46.2 1.194 1.196 65.6 49.1 7.2
Various reports suggest peak activity of the Perseids occurred on
1992 Aug 11.81UT. The next peak is predicted for 1993 Aug 12.05UT
with an uncertainty of 0.1d.
IAUC 5620,5621
Guy M Hurst