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                                                  Circular No. 6079
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian 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 62794505

     R. M. Wagner and R. Bertram, Ohio State University; P. S.
Smith, University of Arizona; and C. R. Shrader, Goddard Space
Flight Center, NASA, report:  "Optical spectra obtained at the
Steward Observatory 2.3-m telescope (range 440-870 nm, resolution
1.4 nm) on Sept. 1.1 UT, and at the Perkins 1.8-m telescope (range
450-570 nm, resolution 1 nm) on Sept. 2.1 and 8.1, of the optical
counterpart of GRO J1655-40 exhibit dramatic variations in both the
intensity and profile of emission lines arising from H-alpha (656.3
nm), H-beta (486.1 nm), He II (468.6 nm), and N III (464.0 nm).  On
both Sept. 1 and 2, the spectrum consists of sharp, unresolved,
emission lines (FWHM </= 550 km/s) due to H-alpha (equivalent width
0.3 nm) and He II (equivalent width 0.7 nm).  H-beta is weak or
completely absent.  In addition, many emission lines due to
permitted O II are present in the region 460-470 nm.  These emission
lines and several interstellar absorption lines are superposed on a
red continuum (V-R = +1.13).  By Sept. 8, the spectrum is characterized
by strong Balmer emission lines and weaker lines of He II and
N III.  The profiles of H-alpha and H-beta both exhibit a double-
peaked structure.  The FWHM and equivalent width of H-beta emission
are about 1600 km/s and 1.6 nm, respectively.  To our knowledge,
such dramatic emission-line profile and intensity variations have
not been observed in any previous x-ray nova or transient.   Our
spectra obtained on Sept. 1-2 and 8 bracket the second outburst of
hard x-ray emission observed on Sept. 6 (IAUC 6075).  No anomalous
emission lines, analogous to the Doppler-shifted emission lines of
SS 433 (and which might coincide with the appearance of the extended
relativistic radio structure; IAUC 6073), have been noted.  However,
our limited spectral coverage and the extreme southern declination
of the object make observations from the northern hemisphere
difficult.  Additional optical spectroscopy from southern-hemisphere
sites would be valuable."

     A. Sanchez-Lavega, Universidad del Pais Vasco, along with J.
Gomez, J. Lecacheux, F. Colas, and I. Miyazaki, reports that
continuous CCD imaging of Saturn at several wavelengths from 0.4 to
1.0 micron has been performed at the Pic-du-Midi 1.05-m telescope,
and in Spain and Japan with 0.4-m telescopes, showing (at least
since mid-July) the presence of a white spot preceded by a dark
column in Saturn's equatorial zone -- which on Sept. 10.01 UT was
at longitude 65o (System I), with a drift rate (relative to System
I) of +10o.2/day between July 28 and Sept. 10.

1994 September 16              (6079)            Daniel W. E. Green

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