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IAUC 6501: GRO J1655-40; SGR 1806-20; C/1996 Q1

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                                                  Circular No. 6501
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
BMARSDEN@CFA.HARVARD.EDU or DGREEN@CFA.HARVARD.EDU (science)
Phone 617-495-7244/7440/7444 (for emergency use only)


GRO J1655-40
     B. A. Harmon, C. R. Robinson, G. J. Fishman, S. N. Zhang, and
W. S. Paciesas, report for the Compton Observatory BATSE Team:
"Hard x-ray flux from the superluminal jet source GRO J1655-40 has
been increasing since mid-October, and has approximately doubled in
intensity since Oct. 26, with fluxes near 1.0 Crab on Oct. 30-31
(20-100 keV).  This activity follows an extended, bright, and
highly-variable outburst (IAUC 6436) between June and Sept.
Spectra obtained between Oct. 26 and 30 are adequately fit with a
power law between 20 and 200 keV, with photon index changing from
-2.6 to -2.9 (+/- 0.1) as the source brightened."


SGR 1806-20
     C. Kouveliotou, Universities Space Research Association; G. J.
Fishman, C. A. Meegan, Marshall Space Flight Center, NASA; J. van
Paradijs, University of Amsterdam and University of Alabama in
Huntsville (UAH); M. S. Briggs and G. Richardson, UAH; and K.
Hurley, University of California, Berkeley, report:  "The BATSE has
triggered on renewed activity from the soft gamma-ray repeater SGR
1806-20 on Oct. 30.95220 and on Oct. 31.54094 and 31.97024 UT.  The
fluence and peak flux of the first event are 10E-7 erg cmE-2 and
10E-6 erg cmE-2 sE-1, respectively.  The reactivation of the source
has initiated several Target of Opportunity observations with other
satellites and groundbased observatories; currently RXTE has
detected several bursts from the source and is observing during
Nov. 6.  We have changed the BATSE trigger criteria to trigger on
(weaker) bursts during the RXTE observations.  We strongly
encourage follow-up observations in other wavelengths."


COMET C/1996 Q1 (TABUR)
     Total magnitude estimates (visual unless otherwise noted):
Oct. 31.76 UT, 8.7 (H. Mikuz, Ljubljana, Slovenia, 0.20-m f/2
Baker-Schmidt camera + V filter + CCD); Nov. 1.80, 8.3 (A. Pereira,
Cabo da Roca, Portugal, 0.25-m reflector); 1.98, 9.5 (J. E. Bortle,
Stormville, NY, 0.41-m reflector); 2.75, 8.7 (Mikuz); 2.75, 9.2 (B.
H. Granslo, near Tryvann, Oslo, Norway, 0.20-m reflector); 3.99,
9.5 (Bortle); 4.74, 8.6 (V. Znojil, Brno, Czech Republic, 25x100
binoculars).

                      (C) Copyright 1996 CBAT
1996 November 6                (6501)            Daniel W. E. Green

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