[IAUC] IAUC 9006: V1647 Ori; C/2008 R7 [25139-2009/08-R1]

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                                                  Circular No. 9006
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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V1647 ORIONIS
     D. K. Ojha, S. K. Ghosh, and S. S. Kaurav, Tata Institute of
Fundamental Research, Mumbai; B. C. Bhatt and D. K. Sahu, Indian
Institute of Astrophysics, Bangalore; and A. Tej, Indian Institute
of Space Science and Technology, Thiruvananthapuram, report the
following optical and near-infrared magnitudes of the young
eruptive star V1647 Ori (cf. IAUCs 8284, 8354, 8396, 8600, 8681,
8694), made with the 2-m Himalayan Chandra telescope (+ HFOSC
spectrograph and NIR camera) at Hanle (Ladakh) and the 2-m IUCAA
Girawali telescope (+ IFOSC spectrograph) at Girawali (Pune):
Sept. 14 UT, V = 18.92 +/- 0.03, R = 17.03 +/- 0.02, I = 14.91 +/-
0.01; Oct. 19, J = 10.64 +/- 0.01, H = 9.01 +/- 0.01, K = 7.63 +/-
0.01 (measured in a 7".2-radius aperture); Nov. 3, V = 18.91 +/-
0.03, R = 17.09 +/- 0.02.  No significant variation in brightness
of V1647 Ori was seen during the period of about two months since
the recent new outburst phase (cf. IAUCs 8968, 8969).  In
comparison with the last reported quiescent phase (cf. Ojha et al.
2006, MNRAS 368, 825), there has been a brightening of about 3
magnitudes in R, and the infrared colors suggest that circumstellar
matter of A_v about 7.5 mag has probably been cleared during this
recent outburst.  Flux-calibrated optical spectra of V1647 Ori
obtained from Sept. 14-Dec. 5 show strong H_alpha emission with
blue-shifted P-Cyg absorption and the Ca II triplet lines in
emission.  The dip in the P-Cyg profile appears to occur around
655.2 nm, which indicates an in-fall velocity of the order of about
500 km/s.  The equivalent widths of the H_alpha and Ca II lines are
about -2.5 and -1.0 nm, respectively, which are similar to the
values seen in the previous outburst (Ojha et al., op.cit.).
Regular monitoring of V1647 Ori is underway in optical and
near-infrared wavebands.


COMET C/2008 R7 (SOHO)
     Further to IAUC 9003, an additional near-sun Kracht-group
presumed comet was found by R. Kracht on SOHO website images
("discovery" image tabulated below).  C/2008 R7 was stellar in
appearance in C3, C2, and COR2-A images, peaking at mag about 5.5
around Sept. 6.83 UT.  Kracht suggests that C/2008 R7 may be
identical with C/2002 S5, though B. G. Marsden notes that identity
with C/2002 S11 is also possible (despite its proposed association
with C/2008 G6).

 Comet       2008 UT       R.A.(2000)Decl.   Inst.  F    MPEC
 C/2008 R7   Sept. 6.447   10 52.3  + 7 37   C3/2*  RK   2008-S67

                      (C) Copyright 2008 CBAT
2008 December 22               (9006)            Daniel W. E. Green