Circular No. 5359 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. Telephone 617-495-7244/7440/7444 (for emergency use only) TWX 710-320-6842 ASTROGRAM CAM EASYLINK 62794505 MARSDEN or GREEN@CFA.BITNET MARSDEN or GREEN@CFAPS2.SPAN COMET SHOEMAKER-LEVY (1991z) E. Bowell, Lowell Observatory, communicates the following pre- cise positions, measured by S. J. Bus, of a new comet discovered by C. S. Shoemaker, E. M. Shoemaker, and D. H. Levy with the 0.46-m Schmidt telescope at Palomar. The object is described as condensed. 1991 UT R.A. (1950) Decl. m1 Oct. 2.30243 0 23 38.25 - 7 29 11.2 16 3.30625 0 22 48.57 - 7 25 13.8 PERIODIC COMET HARTLEY 2 (1991t) Ephemeris from orbital elements on MPC 18598: 1991 ET R.A. (1950) Decl. Delta r m1 Oct. 11 9 06.46 +11 23.0 1.060 1.047 8.9 21 9 33.52 + 7 43.5 31 9 56.53 + 4 22.5 1.154 1.192 10.0 Nov. 10 10 15.81 + 1 21.2 20 10 31.51 - 1 19.8 1.201 1.369 10.9 30 10 43.65 - 3 39.8 Dec. 10 10 52.10 - 5 37.6 1.204 1.559 11.8 20 10 56.64 - 7 10.8 30 10 57.10 - 8 16.6 1.180 1.752 12.5 Total visual magnitude estimates (cf. IAUC 5340): Sept. 10.11 UT, 8.0 (H. Mikuz, Ljubljana, Yugoslavia, 20x60 binoculars); 18.86, 8.2 (A. Pearce, Scarborough, W. Australia, 20x80 binoculars); 20.15, 8.1 (J. Shanklin, Cambridge, England, 20x80 binoculars); 27.22, 8.6 (A. Pereira, Cabo da Roca, Portugal, 0.15-m reflector); Oct. 4.07, 8.7 (Mikuz). FG SERPENTIS Visual magnitude estimates (cf. IAUC 5311): Aug. 6.1 UT, 12.2 (J. E. Bortle, Stormville, NY); 16.90, 12.5 (E. Schweitzer, Stras- bourg, France); Sept. 3.84, 11.9 (M. Verdenet, Bourbon-Lancy, France); 6.87, 12.3 (A. Boattini, Florence, Italy); Oct. 3.77, 11.7 (Boattini). 1991 October 4 Daniel W. E. Green