IAUC 5909: OJ 287; 1993e

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                                                  Circular No. 5909Central Bureau for Astronomical TelegramsINTERNATIONAL ASTRONOMICAL UNIONPostal Address: Central Bureau for Astronomical TelegramsSmithsonian 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 62794505MARSDEN@CFA or GREEN@CFA (.SPAN, .BITNET or .HARVARD.EDU)OJ 287     M. Kidger, Instituto de Astrofisica de Canarias; L. Takalo,Tuorla Observatory; and the 'OJ94 team' report:  "Recent monitoringof OJ 287 shows it to have reached its brightest level since 1984.CCD observations by Kidger with the LAC-80 telescope (Teide Observatory,Tenerife) give the following V magnitudes:  Nov. 27.131 UT,15.11; Dec. 6.090, 14.68; 6.139, 14.37; 6.176, 14.50; 7.279, 15.13.J. Mattei (AAVSO) and D. Wills (University of Texas) report thefollowing visual magnitude estimates:  Dec. 7.284, [15.3 (D. York,Abiquiu, NM); 8.225, [14.9 (York); 9.241, 14.6 (York); 9.25, 14.80(P. Boltwood, Ontario, CCD + V filter); 10.246, 15.0 (York); 14.031,15.1 (G. Poyner, Birmingham, England); 14.263, 15.4 (York); 15.254,15.3 (York); 14.660, [15.4 (S. Sakuma, Kanagawa-ken, Japan).  Amajor outburst of this object was predicted for 1994 July/August bySillanpaa et al. (1988, Ap.J. 325, 628) on the basis that theoutbursts are caused by the 11.6-yr orbital period of a binary blackhole.  A more recent examination of the lightcurve (Kidger et al.1992, A.Ap. 264, 32) suggests that the true period is rather shorterand gave a revised prediction for the maximum of the outburst inearly 1994 March.  The recent data suggest that the rise to maximummay now have initiated, or that this may be a small precursor outburstsimiliar to the one observed before the main outburst in 1983.Lightcurve monitoring is urgently requested at all wavelengths toestablish whether or not this is the predicted outburst and topermit the observed lightcurve behavior to be contrasted with modelsof the predicted propagation at different frequency ranges."PERIODIC COMET SHOEMAKER-LEVY 9 (1993e)     D. K. Yeomans and P. W. Chodas, Jet Propulsion Laboratory,report that they closely confirm the computations by B. G. Marsden onIAUC 5906.  They note that the Jupiter impact times in July 1994are still uncertain by a few hours, but that the new times showthat the impact points (defined to be the points where the cometaryfragments reach the 1-bar level in Jupiter's atmosphere), thoughstill on Jupiter's dark side, are significantly closer to the morningterminator than has previously been indicated.  The jovigraphiclatitudes at impact range from -47o to -49o, and the earth-Jupiter-comet angles at impact range from 95o to 100o.1993 December 17               (5909)            Daniel W. E. Green

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