Circular No. 4577 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 MARSDEN or GREEN@CFA.BITNET MARSDEN or GREEN@CFAPS2.SPAN X-RAY PULSAR F. Makino and the Ginga Team, Institute of Space and Astronautical Science, Tokyo, report that the x-ray outburst near the position of Cep X-4 (IAUC 4575) is due to an x-ray pulsar with a pulsation period of 66.25 s. The source shows erratic short-term variations superposed on the regular pulsations. The object is similar to the transient pulsar X0332+52. The averaged intensity was still about 100 mCrab as of Apr. 4. S PERSEI B. A. Skiff, Lowell Observatory, reports that the steady rise in brightness noted by R. Stencel (IAUC 4556) has slowed considerably in the last several weeks, from about 0.010 mag/day in February to near constancy at the end of March. This is apparent from the following representative differential measurements (uncertainty 0.005 mag) relative to HD 14415, obtained with the Lowell 0.53-m telescope and a Stromgren y filter: Feb. 8.14 UT, 0.934; 20.13, 0.804; Mar. 1.10, 0.722; 8.13, 0.694; 18.13, 0.678; 27.12, 0.656. VARIABLE IN ANDROMEDA G. M. Hurst, Basingstoke, England, communicates the following precise measurement by A. Young, Burwash, of the object reported on IAUC 4570 from a Mar. 26 exposure with a 0.57-m reflector: R.A. = 2h26m22s.14, Decl.= +39 49'21".0 (equinox 1950.0); a measurement by B. Manning, Stakenbridge, of a photograph by M. Mobberley yields the end figures 22s.21, 19".9. Hurst reports that the object appears on the Palomar Sky Survey (1951 Dec. 21) at B = 18-19 and on a Papadopoulos chart (1976 Oct. 19) at mpv = 12.5. It is absent from the Lick Atlas chart (1954 Sept. 26), another Papadopoulos chart (1976 Aug. 31, [13.5) and an exposure by M. Oates (1987 Oct. 29, [14.0). He suggests that it is a Mira-type variable with a range of about 10 mag. Visual magnitude estimates: Mar. 26.84 UT, 10.8 (Hurst); 27.84, 11.1 (Hurst); 28.78, 11.4 (A. Boattini, Florence, Italy); 31.84, 11.3 (Hurst); Apr. 1.06, 11.0 (C. Scovil, Stamford, CT). NOVA IN THE LARGE MAGELLANIC CLOUD Visual magnitude estimates by A. Pearce, Woodlands, Western Australia: Apr. 4.62 UT, 12.4; 5.48, 12.5; 6.50, 12.2. 1988 April 6 (4577) Brian G. Marsden
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