[IAUC] IAUC 9011: eta Car; C/2008 R8-R12 [25139-2009/08-R1]

IAUC mailing list quai en cfa.harvard.edu
Mie Ene 21 01:03:31 ARST 2009


                                                  Circular No. 9011
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS en CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT en CFA.HARVARD.EDU (science)
URL http://www.cfa.harvard.edu/iau/cbat.html  ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)


eta CARINAE
     A. Damineli, Instituto de Astronomico e Geofisico,
Universidade de Sao Paulo, reports that spectroscopic observations
collected at the Southern Astrophysical Research Telescope (La
Serena, Chile) by Damineli, J. Steiner, J. H. Groh, and L. Fraga
indicate that eta Car reached the phase of minimum excitation on
Jan. 11, on schedule with the predictions (Damineli et al. 2008,
MNRAS 384, 1649).  This supports the 2023-day period and the binary
nature of the system.  The doubly ionized forbidden lines and the
narrow components of He I and [N II] lines disappeared from the
spectrum.  P-Cyg absorption in permitted transitions (He I, H I,
and Fe II) became more enhanced.  The He II 468.6-nm line, which
had been increasing rapidly through 2008 December, has now
collapsed abruptly to about 300 milliAngstroems, the same level as
it was a month before.  The radial velocity reached -3204 km/s and
seems to be still shifting toward the blue.  Such results are
corroborated by observations taken at Observatorio do Picos dos
Dias (Brazil) by M. Teodoro; at the Complejo Astronomico el
Leoncito (Argentina) by E. F. Lajuz, F. Gonzalez, and R. Gamen; at
the European Southern Observatory 2.2-m telescope by M. Borges
Fernandes, C. B. Pereira, C. A. P. C. O. Torres, and M. I. Zevallos
Herencia; and at Las Campanas Observatory by N. Morrell.  Figures
and additional details can be found at the following website URL:
www.etacarinae.iag.usp.br.


COMETS C/2008 R8-R12 (SOHO)
     Further to IAUC 9006, additional near-sun presumed comets have
been found on SOHO website images -- all Kreutz sungrazers except
for C/2008 R8 (non-group).  C/2008 R8 (peak mag about 7), C/2008 R9
(mag about 7), and 2008 R11 (mag about 6.5) were small and stellar
in appearance.  C/2008 R10 was elongated (mag about 5.5) in C3
images, and quite diffuse with a very faint short tail in C2 images.
C/2008 R12 was slightly elongated (mag about 6-6.5) in C3 images,
and diffuse with a very faint, diffuse, short tail in C2 images.

 Comet       2008 UT       R.A.(2000)Decl.   Inst.  F    MPEC
 C/2008 R8   Sept. 3.629   10 46.2  + 6 02   C2     RK   2008-X24
 C/2008 R9         4.904   10 32.1  + 5 34   C3     JR   2008-X24
 C/2008 R10        7.904   10 38.0  + 4 00   C3/2   RK   2008-X24
 C/2008 R11        7.904   10 43.1  + 4 35   C3     BZ   2008-X25
 C/2008 R12       11.905   10 54.5  + 2 40   C3/2   BZ   2008-X25
 C/2008 R13       14.596   11 16.4  + 2 29   C3     HS   2008-X25

                      (C) Copyright 2008 CBAT
2009 January 20                (9011)            Daniel W. E. Green



Más información sobre la lista de distribución Iauc