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IAUC 7165: 1999 J2; 4U 1630-47

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                                                  Circular No. 7165
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, 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)
URL http://cfa-www.harvard.edu/iau/cbat.html  ISSN 0081-0304
Phone 617-495-7244/7440/7444 (for emergency use only)


COMET 1999 J2
     The Lowell Observatory Near-Earth Object Search (LONEOS)
reports its discovery of a comet.  The following CCD positions are
available:

     1999 UT             R.A. (2000) Decl.        m1    Observer
     May  13.40333   16 58 28.92   +63 43 15.4   16.0   Skiff
          13.42119   16 58 27.59   +63 43 15.7            "
          13.43905   16 58 26.12   +63 43 15.2            "
          13.87581   16 57 50.18   +63 43 06.8   15.5   Tichy
          13.87745   16 57 50.08   +63 43 07.3            "
          13.87869   16 57 49.95   +63 43 06.9            "

B. A. Skiff (LONEOS).  0.59-m LONEOS Schmidt telescope + R filter.
   Measurer B. W. Koehn.  Well-condensed nucleus in a coma of
   diameter about 15", with a faint tail extending about 40" in
   p.a. 30 deg.
M. Tichy and Z. Moravec (Klet).  0.57-m f/5.2 reflector.  10" coma.


4U 1630-47
     M. L. McCollough, Universities Space Research Association and
Marshall Space Flight Center (MSFC); B. A. Harmon, MSFC, NASA; S.
Dieters, University of Alabama, Huntsville; and R. Wijnands,
Astronomical Institute, University of Amsterdam, communicate:  "The
CGRO BATSE earth-occultation monitoring (20-100 keV) indicates that
the recurrent blackhole x-ray transient 4U 1630-47 (cf. IAUC 6389,
6822) has shown increased activity.  It has risen over the last 18
days from 70 mCrab (20-100 keV) on Apr. 20 to 140 mCrab on May 7.
It has a hard spectrum (power-law index -2.6 +/- 0.2) with emission
extending past 200 keV.  A public target-of-opportunity RXTE PCA
observations on May 8.05 UT showed the source to be at 75 mCrab
(2-20 keV) with a spectrum described by a power law with an index
of -1.6 +/- 0.06 and no evidence of a blackbody component.  A
strong quasiperiodic oscillation was found in the data (2-60 keV)
with a centroid frequency of 0.855 +/- 0.005 Hz, FWHM of 0.13 +/-
0.01, and fractional rms amplitude of 16.3 +/- 0.5 percent.  This
renewed activity of 4U 1630-47 follows a significant outburst in
Feb. 1998 (IAUC 6822) and does not fall within the expected about
690-day outburst cycle of this source.  With an outburst, radio
emission is expected, and observations at radio wavelengths is
encouraged."

                      (C) Copyright 1999 CBAT
1999 May 13                    (7165)            Daniel W. E. Green

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