# Gravastar Shadows

@inproceedings{Sakai2014GravastarS, title={Gravastar Shadows}, author={Nobuyuki Sakai and Hiromi Saida and Takashi Tamaki}, year={2014} }

Direct observation of black holes is one of the grand challenges in astronomy. If there are supercompact objects which possess unstable circular orbits of photons, however, it may be difficult to distinguish them from black holes by observing photons. As a model of super-compact objects, we consider a gravastar (gravitational-vacuum-star) which was originally proposed by Mazur and Mottola. For definiteness, we adopt a spherical thin-shell model of a gravastar developed by Visser and Wiltshire…

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