Circular No. 4264 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 V822 CENTAURI (CENTAURUS X-4) S. A. Ilovaisky and C. Chevalier, Observatoire de Haute- Provence; M. van der Klis, Space Science Department, European Space Agency; J. van Paradijs, Astronomical Institute, University of Amsterdam; and H. Pedersen, European Southern Observatory, telex: "We obtained 240 V-band CCD frames of the optical counterpart of the soft x-ray transient Cen X-4 during x-ray quiescence with the 1.54-m Danish telescope at La Silla in 1985 Mar.-July and 1986 May. Analysis of the frames reveals a 0.2-mag modulation with a period of 15.0978 +/- 0.0015 hr. The lightcurve shows two unequal minima and unequal maxima. During observations in 1986 Apr. obtained with the same instrument, V822 Cen probably showed a 'mini-outburst'; it was then 0.5 mag brighter, substantially bluer, and remarkably active with 'flares' of up to 0.5 mag in 30 min, masking the periodic modulation observed when the object is fainter." 28 TAURI J. Chauville and D. Ballereau, Meudon Observatory, report: "A series of 3 spectra obtained of the Be shell star HD 23862 = 28 Tau (Pleione) on Sept. 29 and Oct. 3-4 on blue-ranged IIaO plates (1.23 nm/mm dispersion) show that the shell has apparently undergone significant changes in the past several months. The H shell lines are visible from H-beta up to H10-H13; other lines are wide and disappear at H16. Shell lines are slightly blue-winged. Emission is visible on H-beta and H-gamma wings, with v/r = 1. Shell lines of other elements have almost completely disappeared; only the strongest Fe II lines are still visible. Perhaps the shell episode which began by the mid-1970s is ending. Further spectroscopic and photometric observations would be useful." DRACONID METEORS D. Levy, Tucson, AZ, communicates that he, P. Collins, J. V. Scotti, and M. Magee observed only 7 Draconid meteors (cf. IAUC 4251) during Oct. 9.08-9.25 UT under clear to partly-cloudy skies. H. Povenmire, Indian Harbour Beach, FL, reports that only one possible candidate was observed by the Florida Fireball Patrol during Oct. 8.0-8.2. E. Stomeo, Lido, Italy, writes that R. Haver, Rome, observed 2 Draconids during Oct. 8.75-9.00. 1986 October 23 (4264) Daniel W. E. Green
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