[IAUC] IAUC 8694: C/2006 A4-A7, B2-B4, E2, F3; V1647 Ori [25139-2006/04-R1]

Vie Jun 22 17:08:12 ART 2007

                                                  Circular No. 8694
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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COMETS C/2006 A4-A7, B2-B4, E2, F3 (SOHO)
     Additional comets have been found on SOHO website images (cf.
IAUC 8679) -- all being Kreutz sungrazers except for C/2006 B4
(Meyer group) and for C/2006 E2 and C/2006 F3 (Marsden group).
C/2006 A4 is described by K. Battams as very faint and diffuse.
C/2006 A5 had a bright coma that "evaporated" quickly in the C2
images, with a tail that "lingered for a long time", being longer
than 1 deg on Jan. 5.612 UT at about 4 solar radii; in C3 images,
the comet was still brightening when at mag perhaps -1.5 on Jan.
5.112 at 11.6 solar radii, showing a bright, thin tail, but it was
at mag about 2.9 and fading fast by the time it reached 7 solar
radii.  The other comets were stellar in appearance.  Peak
magnitudes:  C/2006 A6, 6.3, Jan. 10.431, 10.8 solar radii; C/2006
A7, 5.8, Jan. 12.738, 11.1 solar radii; C/2006 B3, 4.3, Jan.
22.612, 10.4 solar radii.  C/2006 B2 and C/2006 F3 were very small
and faint.  C/2006 B4, at mag approximately 7, was slightly
elongated in the direction of motion.  C/2006 E2 was extremely
faint and slightly diffuse in C2 images (stellar in C3).

 Comet        2006 UT       R.A.(2000)Decl.   Inst.  F    MPEC
 C/2006 A4    Jan.  2.904  19 04.2   -25 26   C3/2   RM   2006-F43
 C/2006 A5          4.096  19 15.1   -27 53   C3/2   TH   2006-F43
 C/2006 A6         10.071  19 40.1   -24 21   C3     TH   2006-F43
 C/2006 A7         12.431  19 49.2   -24 12   C3     SF   2006-F43
 C/2006 B2         20.321  20 22.8   -21 51   C3     HS   2006-F44
 C/2006 B3         21.654  20 38.1   -23 16   C3     RK   2006-F44
 C/2006 B4         26.496  20 37.2   -17 18   C2     HS   2006-F44
 C/2006 E2    Mar. 15.096  23 50.5   - 1 26   C3/2   RM   2006-F50
 C/2006 F3         26.101   0 23.1   + 4 13   C2     TH   2006-F50


V1647 ORIONIS
     V. Venkat and B. G. Anandarao, Astronomy and Astrophysics
Division, Physical Research Laboratory, Ahmedabad, report
near-infrared photometry of V1647 Ori undertaken at Mt. Abu
Observatory's 1.2-m telescope (+ NICMOS infrared array) on Feb. 27,
revealing magnitudes J = 14.6, H = 11.7, and K' = 9.7.  These
magnitudes are close to the 2MASS values and fainter than their own
values from 2005 Dec. 3 (Ojha et al. 2006, MNRAS, in press;
http://xxx.lanl.gov/abs/astro-ph/?0602044).  It appears therefore
that, following its EXor-like eruption (IAUC 8289) that lasted more
than 24 months (cf. IAUC 8600; 8681), the star may be near its
pre-eruptive state.

                      (C) Copyright 2006 CBAT
2006 March 29                  (8694)            Daniel W. E. Green