2010CBET.2164....1M

D. Milisavljevic and R. Fesen, Dartmouth College, report that a low- dispersion spectrum (range 430-790 nm) of 2009mx (cf. CBETs 2095, 2120), taken on Feb. 6.4 UT with the 2.4-m Hiltner telescope (+ CCDS) at MDM Observatory, supports a type-Ia supernova classification. Comparison with a library of supernova spectra using the "Supernova Identification" tool (SNID; Blondin and Tonry 2007, ApJ., 666, 1024) provides a good match with the type-Ia event 1991bg at approximately 54 days post-maximum light. Spectra of 2009my (CBETs 2095, 2120) show it to be a type-II supernova approximately 2 months after maximum light; SNID comparison templates best match the type-IIP event 2006bp at 65 days post-maximum.