[IAUC] IAUC 9189: C/2010 X1; P/2010 V1 [25139-2011/04-R1]

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                                                  Circular No. 9189
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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COMET C/2010 X1 (ELENIN)
     Leonid Elenin (Lyubertsy, Russia) reports his discovery of a
comet on four 240-s unfiltered CCD exposures taken remotely with a
0.45-m f/2.8 astrograph at the ISON-NM observatory near Mayhill,
NM, USA, on Dec. 10.435 UT (discovery observation tabulted below).
After posting on the Minor Planet Center's "NEOCP" webpage, other
cometary astrometrists have noted the object's cometary appearance.
A. Sergeyev (Kharkov, Ukraine) and A. Novichonok (Kondopoga, Russia)
write that four stacked 300-s CCD images taken with a 1.5-m f/8
reflector at the Majdanak Observatory in Uzbekistan on Dec. 11.0
show a teardrop-shaped, very diffuse coma of diameter 6" (total
magnitude 19.1; magnitude of nuclear condensation 20.7) and a tail
of length 10"-12" in p.a. 298 deg.  W. H. Ryan obtained R-band CCD
images with the Magdalena Ridge Observatory's 2.4-m f/8.9 reflector
on Dec. 12.47-12.49 that show the object to be diffuse with a tail
in p.a. about 315 deg.  R. S. McMillan, J. V. Scotti, and M. L.
Terenzoni report that five 60-s R-band images taken through thin
clouds on Dec. 12.5 with the Steward Observatory 2.3-m f/3 Bok
telescope (+ 90Prime CCD camera) at Kitt Peak in 2" seeing show a
coma diameter of about 7" and a tail extending 10" in p.a. 290 deg.
H. Sato (Ota-ku, Tokyo, Japan) obtained CCD images remotely with a
0.50-m f/6.8 reflector at the RAS Observatory near Mayhill on Dec.
12.51 that show an 8" coma and a 45" tail toward p.a. 285 deg.

     2010 UT             R.A. (2000) Decl.       Mag.   Observer
     Dec. 10.41707   11 58 06.29   - 0 34 20.1   19.5   Elenin

The available astrometry, the following preliminary parabolic
orbital elements by G. V. Williams, and an ephemeris appear on MPEC
2010-X101.  It is possible that this comet is of short period.

     T = 2010 Apr.  1.810 TT          Peri. = 181.193
                                      Node  = 319.659   2000.0
     q = 5.15165 AU                   Incl. =   1.456


COMET P/2010 V1 (IKEYA-MURAKAMI)
     Additional astrometry has shown that this comet (cf. IAUCs
9175, 9176, 9183, 9184) is of short period; the following orbital
elements by G. V. Williams are from MPEC 2010-X75:  Epoch 2010 Oct.
11.0 TT, T = 2010 Oct. 12.7260 TT, e = 0.481213, q = 1.575188 AU,
Peri. = 152.0519 deg, Node = 3.7787 deg, i = 9.3836 deg (equinox
2000.0), P = 5.29 years.

                      (C) Copyright 2010 CBAT
2010 December 17               (9189)            Daniel W. E. Green