[IAUC] IAUC 9211: C/2011 K1; V5588 Sgr [25139-2011/04-R1]

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                                                  Circular No. 9211
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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CBATIAU en EPS.HARVARD.EDU           ISSN 0081-0304
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Prepared using the Tamkin Foundation Computer Network


COMET C/2011 K1 (SCHWARTZ-HOLVORCEM)
     A comet that shows a coma and tail in co-added images in a
crowded star field, in images taken around May 26.27 and 27.3 UT
with the Tenagra III 0.41-m astrograph, was discovered by Paulo R.
Holvorcem (Porto Seguro, Bahia, Brazil) and Michael Schwartz
(Patagonia, AZ, U.S.A.); their follow-up images taken during May
28.24-28.31 with a 0.81-m telescope show a coma diameter of 10"
with a broad, 13"-long tail toward p.a. 37 deg (their discovery
observation is tabulated below).  Following posting on the Minor
Planet Center's NEOCP webpage, other CCD astrometrists have
commented on the object's cometary appearance.  R-band images taken
by W. H. Ryan and E. V. Ryan (Magdalena Ridge Observatory 2.4-m
f/8.9 reflector) on May 28.3 and 31.6 show a tail in p.a. about 45
deg.  L. Buzzi (Varese, Italy, 0.38-m reflector) finds a faint,
round, 10" outer coma on May 29.0 and 30.3.  Stacked images taken
by R. Holmes (Ashmore, IL, U.S.A., 0.81-m astrograph) on May 30.3
are found by T. Vorobjov and S. Foglia to show a distinct 25" tail
in p.a. 36 deg and a round coma 5" across.

     2011 UT             R.A. (2000) Decl.       Mag.   Observer
     May  26.25521   17 07 31.83   -16 40 15.9   19.5   Schwartz

The available astrometry, preliminary orbital elements by G. V.
Williams (T = 2011 Apr. 19.3064 TT, q = 3.352986 AU, e = 0.932942,
Peri. = 166.6276, Node = 70.7828, i = 122.0377, equinox 2000.0),
and an ephemeris appear on MPEC 2011-L04.


V5588 SAGITTARII
     R. J. Rudy and R. W. Russell, Aerospace Corporation; and M.
Sitko, Space Science Institute, report 0.8- to 5.5-micron
spectroscopy of V5588 Sgr on Apr. 28 UT using the SpeX instrument
on the Infrared Telescope Facility (IRTF).  As noted by Arai et al.
(IAUC 9203), V5588 Sgr is an "Fe II"-type nova.  The IRTF data show
both the 1- and 1.6-micron Fe II features.  The H I lines now
display two distinct emission components:  the narrow component
with FWHM = 900 km/s (reported by Arai et al.) and a broad, flat-
topped component with a FWZI = 3700 km/s.  The He I line profiles,
unlike those of H I, are comprised almost entirely of the broad
component.  The spectrum also shows strong neutral lines of
nitrogen but not of carbon.  The Ca II infrared triplet is present.
The reddening, as derived from the O I lines, is E(B-V) = 1.2 +/-
0.15.  There is no evidence yet for dust formation.

                      (C) Copyright 2011 CBAT
2011 May 31                    (9211)            Daniel W. E. Green