2004IAUC.8449....2M

M. Modjaz, R. Kirshner, and P. Challis, Harvard-Smithsonian Center for Astrophysics; and T. Matheson, National Optical Astrononmy Observatory, report that a spectrogram (range 350-740 nm) of SN 2004gc (cf. IAUC 8442), obtained by M. Calkins on Dec. 8.42 UT with the F. L. Whipple Observatory 1.5-m telescope (+ FAST), shows it to be a supernova of type Ia, with a spectral- feature age (Riess et al. 1997, A.J. 114, 722) of about 3 weeks past maximum brightness. Adopting the NED recession velocity of 9620 km/s for the host galaxy, the supernova expansion velocity, derived from the minimum of Si II (rest 635.5 nm), is about 9400 km/s.