Circular No. 4530 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 X-RAY PULSAR F. Makino, Institute of Space and Astronautical Science, Tokyo, reports on behalf of the Ginga Team: "A new x-ray pulsar was discovered with the x-ray astronomy satellite Ginga in a field of view of 1.5 x 3.7 deg entered at R.A. = 17h22m, Decl. = -36.6. The error box includes the x-ray source GPS 1722-363 (Warwick et al. 1987, preprint) and SNR G351.2+0.1. The pulsation was observed on 1987 Oct. 10 with an average period of 413.9 +/- 0.2 s. The x-ray intensity of the pulsating component was 5.6 x 10**-10 erg cm-2 s-1 (5-37 keV) for about 30 min from Oct. 10.434 UT and gradually decreased to below the detectable level on Oct. 10.740 UT. The pulse profile is singly peaked and weakly energy dependent. The energy spectrum showed a strong iron-line emission and absorption feature." SUPERNOVA 1987A IN THE LARGE MAGELLANIC CLOUD Makino and the Ginga Team also report: "SN 1987A has recently shown a large increase in x-ray intensity. The intensity observed from Ginga on 1987 Dec. 26 was 2.3 +/- 0.6 counts/s in the range 6- 16 keV and 0.9 +/- 0.2 counts/s in the range 16-28 keV. On 1987 Jan. 7 the intensity was 7.8 +/- 0.8 and 1.7 +/- 0.3 counts/s in the respective energy ranges. Another observation on Jan. 12 showed a further increase to 9.7 +/- 0.6 and 1.8 +/- 0.2 counts/s, respectively." COMET BRADFIELD (1987s) J.-C. Merlin, Le Creusot, France, provides the following antitail lengths from 0.30-m Schmidt telescope exposures by G. Klaus, Grenchenberg, Switzerland: 1987 Dec. 13.83 UT, 35' in p.a. 224 deg; 21.79, 70' in p.a. 241 deg. Total visual magnitude estimates: 1987 Dec. 30.40 UT, 6.6 (Y. Sugiyama, Hiratsuka, Japan, 0.16-m reflector); 1988 Jan. 1.10, 6.3 (C. E. Spratt, Victoria, BC, 11 x 80 binoculars); 3.13, 7.4 (A. Hale, Las Cruces, NM, 10 x 50 binoculars; moonlight); 5.76, 6.7 (J. Shanklin, Cambridge, England, 10 x 80 binoculars; 0.9-deg tail in p.a. 69 deg); 8.09, 7.0 (R. A. Keen, Mt. Thorodin, CO, 8 x 40 binoculars; 1-deg tail in p.a. 60 deg); 10.81, 6.9 (Shanklin; tail 1.3 deg in p.a. 73 deg); 11.74, 7.5 (P. Schmeer, Bischmisheim, West Germany, 20 x 80 binoculars); 13.18, 6.8 (C. S. Morris, Whitaker Peak, CA, 10 x 50 binoculars; 4.5-deg tail in p.a. 65 deg; 40' tail in p.a. 270 deg with faint fan passing through north and connecting with the main tail). 1988 January 16 (4530) Brian G. Marsden
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