Herein we exhibit exact, analytic, fully explicit, photon escape cones and the related silhouettes (“shadows”) at arbitrary distance from an extremal ($|a|=m$) Kerr black hole. In contrast to the situation for nonextremal ($0<|a|<m$) Kerr, where one typically has to resort to numerical, and/or graphics based, and/or perturbative investigations, the situation for extremal Kerr is amenable to direct analytic and fully explicit investigation. Interest in these results is twofold: In view of the technical complexity of Kerr spacetime, any fully explicit analytic result (even if only for the special case of extremality) is a significant aid to physical insight. Furthermore a significant fraction of observationally accessible galactic black holes are high spin, relatively close to extremal, objects ($|a|\gtrsim 0.85m$) so the extremal case is a good analytically tractable zeroth order approximation for such objects.

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• Classical black holes
• General relativity