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We have acquired Hubble Space Telescope (HST) and Very Large Telescopenear-infrared spectra and images of supernova (SN) Refsdal after its discoveryas an Einstein cross in Fall 2014. The HST light curve of SN Refsdal matchesthe distinctive, slowly rising light curves of SN 1987A-like supernovae (SNe),and we find strong evidence for a broad H-alpha P-Cygni profile in the HSTgrism spectrum at the redshift (z = 1.49) of the spiral host galaxy. SNe IIn,powered by circumstellar interaction, could provide a good match to the lightcurve of SN Refsdal, but the spectrum of a SN IIn would not show broad andstrong H-alpha absorption. From the grism spectrum, we measure an H-alphaexpansion velocity consistent with those of SN 1987A-like SNe at a similarphase. The luminosity, evolution, and Gaussian profile of the H-alpha emissionof the WFC3 and X-shooter spectra, separated by ~2.5 months in the rest frame,provide additional evidence that supports the SN 1987A-like classification. Incomparison with other examples of SN 1987A-like SNe, SN Refsdal has a blue B-Vcolor and a high luminosity for the assumed range of potential magnifications.If SN Refsdal can be modeled as a scaled version of SN 1987A, we estimate itwould have an ejecta mass of 20+-5 solar masses. The evolution of the lightcurve at late times will provide additional evidence about the potentialexistence of any substantial circumstellar material (CSM). Using MOSFIRE andX-shooter spectra, we estimate a subsolar host-galaxy metallicity (8.3+-0.1 dexand <8.4 dex, respectively) near the explosion site.

SN Refsdal: Classification as a Luminous and Blue SN 1987A-like Type II Supernova