Circular No. 4527 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. TWX 710-320-6842 ASTROGRAM CAM Telephone 617-495-7244/7440/7444 COMET LILLER (1988a) William Liller, Vina del Mar, Chile, reports his discovery of a comet. The following observations are available: 1988 UT R.A. (1950) Decl. m1 Observer Jan. 11.0646 23 50.9 -28 18 13 Liller 12.444 23 50.9 -27 20 Cragg 12.477 23 50.9 -27 19 10.2 McNaught W. Liller (Vina del Mar, Chile). 0.2-m Schmidt. Two 2-min exposures 30 min apart, 2415 film, taken in course of PROBLICOM survey. Object diffuse, coma diameter 1', faint condensation. T. Cragg and R. H. McNaught (Coonabarabran, N.S.W.). 0.32-m reflector. Magnitude estimate on Jan. 12.457 UT (20 x 120 binoculars); coma diameter 6'. Cragg notes nearly stellar nucleus. SUPERNOVA 1987A IN THE LARGE MAGELLANIC CLOUD W. R. Cook, D. Palmer, T. Prince, S. Schindler, C. Starr and E. Stone, California Institute of Technology, report: "Hard x-ray and gamma-ray observations of SN 1987A were made during the period 1987 Nov. 18.6-18.9 UT with the Caltech imaging gamma-ray spectrometer launched by balloon from Alice Springs. Using 2.5 hr of data, we detected the supernova at 4.9-sigma significance in the energy range 40-1300 keV. The spectrum appears to be significantly harder than that of the Crab gamma-ray source, having a photon spectral index of -0.9 if a power-law. The flux values detected below 300 keV are consistent with those measured earlier by the HEXE instrument on the Mir spacecraft (1987, Nature 330, 227). Flux was detected at the 2.6- sigma level from the sum of counts in two energy ranges: 81- keV wide centered on 847 keV and 93-keV wide centered on 1238 keV. A preliminary estimate for the flux in each of these two energy ranges yields (1.1 +/- 0.6) x 10**-3 photons cm-2 s-1." PERIODIC COMET BORRELLY (1987p) Total visual magnitude estimates: 1987 Dec. 24.20 UT, 7.1 (C. Spratt, Victoria, BC, 11 x 80 binoculars; 15' tail in p.a. 45 deg); 28.19, 7.3 (A. Hale, Las Cruces, NM, 0.41-m reflector); 1988 Jan. 1.41, 8.0 (Y. Sugiyama, Hiratsuka, Japan, 0.16-m reflector); 3.16, 7.6 (Hale); 6.45, 8.5 (Sugiyama); 8.45, 8.3 (Sugiyama). 1988 January 12 (4527) Brian G. Marsden
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