Event horizons and ergospheres of a rotating black hole (spin parameter a=Jc/G/M²=0.99); the ring-singularity is located at the equatorial kink of the inner ergosphere at R=a.
<a href="//commons.wikimedia.org/wiki/User:Yukterez" title="User:Yukterez">Yukterez</a> (Simon Tyran, Vienna)
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