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THE ASTRONOMER Electronic Circular No 872     1994 Aug 13  22.00 UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise,  Basingstoke,
Hants, RG22 4PP,England. Telephone/FAX(0256)471074 Int:+44256471074
INTERNET: GMH at AST.STAR.RL.AC.UK  or    GMH at GXVG.AST.CAM.AC.UK
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COMET MACHHOLZ (1994o)
     Donald E. Machholz reports his visual discovery of a comet.
The following observations are available:

     1994 UT             R.A. (2000) Decl.        m1    Observer
     Aug. 13.4215     4 12.9       +62 48        10     Machholz
          13.80190    4 20 30.42   +62 37 18.1          Kojima
          13.80304    4 20 31.66   +62 37 18.1            "
          13.80431    4 20 33.44   +62 37 18.6            "
          13.80535    4 20 35.32   +62 37 11.6            "

D. E. Machholz (Colfax, CA).  0.25-m reflector.  Comet diffuse with
  little condensation; coma diameter perhaps 3'-4'.
T. Kojima (YGCO Chiyoda Observatory).  0.25-m reflector + CCD.  Poor
  conditions in twilight.  Comet diffuse with condensation.
  Communicated by S. Nakano, Sumoto, Japan.

IAUC 6053

JUPITER AND COMET 1993e
     G. Bjoraker, Goddard Space Flight Center, NASA; and T. Herter,
S. Stolovy, G. Gull, and B. Pirger, Cornell University, write:  "We
have detected cometary water in the fireball of fragments G and K
immediately after the plume became visible to observers on Earth.
The observations were performed using the Kuiper Echelle Grating
Spectrometer (spectral resolving power 9000; 5" slit) on the Kuiper
Airborne Observatory.  The G fireball was observed at about July
18.323 UT; the K fragment fireball was observed on July 19.444.
Three H2O lines were observed in emission for both the G and K
fireballs at the following wavelengths:  7.7136, 7.7118, and 7.7090
microns.  Numerous jovian 12CH4 and 13CH4 lines were observed in
emission across our bandpass (7.671-7.722 microns).  This serves as
a thermometer of Jupiter's stratosphere, sounding the 1-microbar to
10-millibar levels.  The radiance in the jovian CH4 lines increased
by a factor of about 25-30 between the pre-crash level and the peak
of the fireball.  The CH4 lines were observed to decay over the
next 2 hr.  The three H2O lines have a distinctively different time
behavior: they essentially disappear over a 30-min period.  Very
high temperatures (T > 500 K) are required to observe these H2O
transitions.  The observing geometry, high temperature, and short
time scale for the disappearance of these H2O lines favor a cometary
(rather than jovian) source.  This, in turn, would confirm that
P/Shoemaker-Levy 9 was a comet and not an asteroid."

IAUC 6053


Martin Mobberley