Supernova 2010ex in Pgc 70222

G. H. Marion, Harvard-Smithsonian Center for Astrophysics and University of Texas; J. Vinko and R. Boros, University of Szeged; and J. C. Wheeler, University of Texas, report that a spectrum (range 430-1000 nm) of 2010ex (cf. CBET 2348), obtained on July 5.3 UT with the 9.2-m Hobby-Eberly Telescope (+ Marcario Low-Resolution Spectrograph) by S. C. Odewahn, shows prominent Si II, S II, Ca II, and Fe II features, characteristic of a type-Ia supernova before maximum brightness. The Ca II infrared triplet has a shallow, but clearly visible, high-velocity component, also suggesting a pre-maximum phase. According to SNID (Blondin and Tonry 2007, Ap.J. 666, 1024), the spectrum is most similar to template spectra from normal type-Ia supernova at a few days before maximum. The redshift, estimated from a narrow H-alpha emission feature from the host galaxy (PGC 70222), is 0.0224, in agreement with the NED value of 0.0228 from Saintonge et al. (2008, A.J. 135, 588). The expansion velocity, obtained from the Si II 635.5-nm feature, is about 10500 km/s.