[IAUC] IAUC 9262: C/2012 S1; C/2013 R1; 2013 UQ_4 y [25139-2012/04-R1]

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                                                  Circular No. 9262
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
New postal address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
CBATIAU en EPS.HARVARD.EDU           ISSN 0081-0304
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Prepared using the Tamkin Foundation Computer Network


COMET C/2012 S1 (ISON)
     M. L. Sitko, University of Cincinnati and Space Science
Institute; R. W. Russell, The Aerospace Corporation; P. Yanamandra-
Fisher, Space Science Institute; and E. Volquardsen and W. Golisch,
NASA Infrared Telescope Facility (IRTF), observed comet C/2012 S1
on Sept. 11 and Oct. 19 using the SpeX spectrograph at the IRTF
between 0.7 and 2.4 microns.  On both dates, the spectrograms
(dominated by scattered light) exhibited spectra that were slightly
redder than the solar spectrum by a factor of approximately
(lambda)_(sun)**0.3, where (lambda)_(sun) is a given wavelength in
the solar spectrum.  The integrated brightness at 2.2 microns
measured through an extraction aperture of 3".0 x 5".2 was [2.2
microns] = 14.5 and 13.1 on the two dates, respectively, with an
estimated uncertainty of +/- 0.3 magnitude.


COMET C/2013 R1 (LOVEJOY)
     R. W. Russell, The Aerospace Corporation; M. L. Sitko,
University of Cincinnati and Space Science Institute; P.
Yanamandra-Fisher, Space Science Institute; and and W. Golisch and
E. Volquardsen, NASA Infrared Telescope Facility (IRTF) report
near-infrared spectroscopy of comet C/2013 R1 using the SpeX
spectrograph at the IRTF on Oct. 19 and 21.  The 0.8- to 2.4-
micron continuum was dominated by scattered light and was
consistent with being slightly redder than the solar spectrum by a
factor of approximately (lambda)_(sun)**0.35, where (lambda)_(sun)
is a given wavelength in the solar spectrum.  The magnitude at 2.2
microns, as measured through an extraction aperture of 3".0 x
5".2, was [2.2 micron] = 12.3 +/- 0.3.  The 3.3- to 3.4-micron
organic emission band that is frequently observed in comet spectra
was present.


2013 UQ_4
     R. P. Binzel, D. Polishook, and R. Bowens-Rubin, Massachusetts
Institute of Technology, report 0.85- to 2.45-micron near-infrared
spectral measurements of 2013 UQ_4 (cf. MPECs 2013-U54, 2013-V01;
orbital elements T = 2014 July 5, q = 1.08 AU, i = 145 deg, e =
0.982) obtained on Oct. 31.5 UT using the NASA 3-m Infrared
Telescope Facility.  An X-type spectral class is found, which for
objects with Jovian Tisserand parameter T_j < 3 typically indicates
an albedo of 0.04 +/- 0.01 (cf. DeMeo and Binzel 2008, Icarus 194,
436).  With no coma apparent, an H magnitude of 12.8 yields an
estimated diameter of 19 +/- 2 km.  No coma is apparent in the
guide-camera images.

                      (C) Copyright 2013 CBAT
2013 November 1                (9262)            Daniel W. E. Green