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The luminous Class I protostar HBC 494, embedded in the Orion A cloud, isassociated with a pair of reflection nebulae, Re50 and Re50N, which appearedsometime between 1955 and 1979. We have found that a dramatic brightening ofRe50N has taken place sometime between 2006 and 2014. This could result if theembedded source is undergoing a FUor eruption. However, the near-infraredspectrum shows a featureless very red continuum, in contrast to the strong CObandhead absorption displayed by FUors. Such heavy veiling, and the highluminosity of the protostar, is indicative of strong accretion but seeminglynot in the manner of typical FUors. We favor the alternative explanation thatthe major brightening of Re50N and the simultaneous fading of Re50 is caused bycurtains of obscuring material that cast patterns of illumination and shadowsacross the surface of the molecular cloud. This is likely occurring as anoutflow cavity surrounding the embedded protostar breaks through to the surfaceof the molecular cloud. Several Herbig-Haro objects are found in the region.

The Brightening of Re50N: Accretion Event or Dust Clearing?