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IAUC 4157: CH Cyg; R Aqr; Sats OF SATURN AND PLUTO

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                                                  Circular No. 4157
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


CH CYGNI
     M. Mikolajewski and B. Wikierski, Torun Observatory, telex:
"With reference to our previous information on CH Cyg (IAUC 4145),
we report further spectral and photometric changes in this object.
While the magnitude has been relatively constant at V = 7.5-7.6,
the U-B and B-V colors were +0.20 and +1.00 on 1985 Dec. 8 and
-0.21 and +0.82 on Dec. 27.  Spectra obtained on Nov. 30 and Dec.
5 show that the intensity of the double-peaked Balmer lines is
twice or thrice that observed a month earlier; the lines have
developed broad emission wings (~ 2500 km/s), similar to those
observed in 1984 Dec.  The permitted emission lines of Fe II have
intensified by the same factor.  He I lines (e.g., 447.2 nm) that
were practically invisible in mid-1985 have strong and complex
emission profiles.  T. Tomov, Bulgarian National Observatory, has
informed us that his spectrograms taken after Dec. 20 show the hot
continuum distinctly, together with the shell absorptions.  The
observed changes are reversed with respect to those seen during
1984 Dec.-1985 Feb. and may suggest an early stage of a new
outburst or the end of a possible eclipse in this system."


R AQUARII
     M. Kafatos, George Mason University; and A. G. Michalitsianos,
Goddard Space Flight Center, report: "IUE observations of this
symbiotic star over the past four years indicate that line emission
from the jet components is variable with period 1.5 yr.  Because
of the distances involved we interpret this variability as 'light
echo', in the sense that ionizing radiation from the inner region
of an accreting disk surrounding the hot star excites the jet
components ~ 10**14 m.  Our most recent observations of 1985 Jan. and
July show that N V, He II and C IV emission has been increasing,
indicating the system is returning to a high-excitation state."


SATELLITES OF SATURN AND PLUTO
     At the recent meetings of the IAU General Assembly in New
Delhi the following new permanent designations and names of natural
satellites were adopted:

     Saturn XVI   Prometheus  = 1980 S27
     Saturn XVII  Pandora     = 1980 S26
     Pluto I      Charon      = 1978 P1.


1986 January 3                 (4157)              Brian G. Marsden

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