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IAUC 6045: JUPITER AND 1993e; 1968D; 1994m

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                                                  Circular No. 6045
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

     P. Galopeau, E. Gerard, and A. Lecacheux, Observatoire de
Paris, Meudon, communicate:  "The jovian synchrotron emission has
been monitored with the Nancay Radio telescope at 1404, 1664, and
3263 MHz during three periods:  Apr. 1-17, May 1-17, and July 9-28.
The observations are made daily near 18h UT and will last until Aug.
23.  A large flux-density increase at all frequencies started on
July 18, reached a maximum between July 20 and 22, and has
decreased since then; the flux-density maximum was 30-40 percent
higher (depending on frequency) than during the April and May runs,
which showed no variation larger than 5 percent.  Thus, there is no
doubt that this outburst is due to the encounter of comet 1993e
with Jupiter."

     S. D. Van Dyk, University of California, Berkeley; S. D. Hyman,
Sweet Briar College; R. A. Sramek, National Radio Astronomy Observatory;
and, K. W. Weiler, Naval Research Laboratory, report the radio
recovery of the type-II supernova 1968D in the nearby spiral galaxy
NGC 6946:  "A candidate source was first found in the summed Very
Large Array (VLA) data collected over several years for the monitoring
of the radio SN 1980K in this galaxy at 20 and 6 cm (1.43 and
4.86 GHz, respectively; see Weiler et al. 1986, Ap.J. 301, 790;
Weiler et al. 1992, Ap.J. 398, 248).  Detection of the source has
been confirmed by additional observations with the VLA in configuration
A, made in 1994 April at these same wavelengths.  SN 1968D has
radio position R.A. = 20h33m55s.298, Decl. = +59o59'09".07 (equinox
1950.0).  The position of the radio nucleus of NGC 6946 has end
figures 49s.245, 58'49".24, giving a nuclear offset for SN 1968D of
45".3 east and 19".8 north, which is in excellent agreement with
the optical offset position obtained near the time of discovery
(IAUC 2057; Barbon et al. 1989, A.Ap. Suppl. 81, 421).  The supernova
has flux densities 0.15 +/- 0.03 and 0.52 +/- 0.03 mJy at 6
and 20 cm, respectively.  The source is therefore nonthermal, with
a steep spectral index R.A. = -1.02 +/- 0.15."

     Total visual magnitude estimates by C. E. Spratt, Victoria, BC
(0.20-m reflector): July 15.29 UT, 8.9; 28.28, 8.8; Aug. 1.27, 8.3.

1994 August 2                  (6045)            Daniel W. E. Green

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