Central Bureau for Astronomical Telegrams
IAUC 4264: V822 Cen (CENTAURUS X-4); 28 Tau; DRACONID METEORS
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Read IAUC 4265
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
Read IAUC 4265
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