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IAUC 8461: N IN M31; 2004gq, 2005A

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                                                  Circular No. 8461
Central Bureau for Astronomical Telegrams
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
URL http://cfa-www.harvard.edu/iau/cbat.html  ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)

     A rather bright apparent nova in M31 has been discovered
independently on an R-band CCD frame taken by K. Hornoch
(Lelekovice, Czech Republic, 0.35-m reflector) on Jan. 7.891 UT and
on unfiltered CCD frames taken by R. Arbour (South Wonston, England,
0.3-m reflector) on Jan. 10.925.  Hornoch's position for the new
object:  R.A. = 0h42m28s.38, Decl. = +41o16'36".2 (equinox 2000.0),
which is 180" west and 28" north of the center of M31; Arbour
provides position end figures 28s.34, 37".6 (estimating the
object's magnitude as about 15).  Available R-band magnitudes
for the nova provided by Hornoch:  2004 Dec. 18.068, [21 (3.5-m
WIYN telescope image taken by P. Garnavich); 2005 Jan. 2.821, [19.8;
6.766, 19.2 (prediscovery image taken at Ondrejov by P. Kusnirak);
6.793, 19.4; 7.891, 17.9; 9.724, 15.6; 9.937, 15.27; 10.749, 15.48
(Kusnirak); 10.766, 15.32; 10.786, 15.27; 10.806, 15.30; 10.908,
15.34; 10.926, 15.31.  A V-band image by Kusnirak taken on Jan.
10.753 yields mag 15.45.

     M. Modjaz, R. Kirshner, and P. Challis, Harvard-Smithsonian
Center for Astrophysics; and T. Matheson, National Optical
Astronomy Observatory, report that a spectrum (range 350-740 nm) of
SN 2005A (cf. IAUC 8459), obtained by E. Falco on Jan. 7.24 UT with
the F. L. Whipple Observatory 1.5-m telescope (+ FAST), shows it to
be a type-Ia supernova, one or two weeks before maximum.  The
supernova expansion velocity, derived from the minimum of Si II
(rest 635.5 nm) and adopting the NED recession velocity of 5738
km/s for the host galaxy, is about 14400 km/s.  Zero-velocity
interstellar Na I D absorption with an equivalent width of about
0.5 nm is detected in a spectrum of SN 2005A taken on Jan. 8.24
by P. Berlind, indicating gas along the line-of-sight in our Galaxy
and thus suggesting reddening by dust.  Schlegel et al. (1998, Ap.J.
500, 525) estimate a Galactic reddening of E(B-V) = 0.03 mag along
the line-of-sight to the host galaxy.
     Modjaz et al. add that a spectrogram of SN 2004gq (cf. IAUC
8452), obtained by Falco on Jan. 7.29 UT, shows it to be a type-Ib
supernova.  The spectrum exhibits conspicuous lines of He I (rest
447.1, 587.6, 667.8, 706.5 nm) and is very similar to spectra of SN
1984L (Harkness et al. 1987, Ap.J. 317, 355), about 3 weeks after
maximum.  SN 2004gq was previously classified (IAUC 8404) as a
type-Ic supernova.

                      (C) Copyright 2005 CBAT
2005 January 11                (8461)            Daniel W. E. Green

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