Circular No. 3912 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 617-864-5758 COMET 1984b M. Clark reports that a plate taken at Mount John Observatory on Jan. 27 failed to confirm the existence of this object. SUPERNOVA IN NGC 4419 R. W. Argyle, Royal Greenwich Observatory, telexes a precise position for this object, derived from an exposure on Jan. 29.988 UT (mpg = 13.0): R.A. = 12h24m24s01, Decl. = +15deg19'53"7 (equinox 1950.0). V0332+53 N. E. White, J. Davelaar, A. N. Parmar and L. Stella, European Space Agency; and M. van der Klis, Astronomical Institute, University of Amsterdam, report that the EXOSAT observations of the second recent outburst of V0332+53 gave a pulse period of 4.37532 +/- 0.0004 s on 1983 Dec. 24. The period therefore did not continue to decrease at the high rate reported during the first outburst (IAUC 3902). However, a similarly high rate of decrease was again present during the second outburst, suggesting that the period variations are due to orbital motion. The flux again decayed over the following week. A third series of observations during 1984 Jan. 19-24 again found the source to be in outburst at a level of 0.04 Crab with the pulse period increasing. Preliminary solutions yield an orbital period P = 34.2 +/- 1.5 days, periastron passage T = 1984 Jan. 20 +/- 4, a sin i = 55(+150)(-10) light seconds, e = 0.35 (+0.25)(-0.10). The outbursts are approximately centered on T. URANUS S. J. O'Meara reports rotation periods for Uranus, derived from seven visual observations of cloud features with the Harvard College Observatory's 0.23-m refractor in 1981; he has not observed such cloud features on other occasions. A polar cloud confirmed the position of Uranus' north pole < 0"7 southwest of the center of the disk. A second cloud suggested a rotation period of 16.0 hr between July 23 and Aug. 28, 16.2 hr from then until Sept. 8 and 16.4 hr during Sept. 8-15. A short-lived cloud detected on Aug. 27 and 28 indicated a 16.0-hr period. These figures are in good agreement with the weighted mean period of 16.31 +/- 0.27 hr deduced by Goody (1982, in "Uranus and the Outer Planets" , p. 143) from spectroscopic observations and dynamical considerations. 1984 February 1 (3912) Brian G. Marsden
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