. "black-hole horizon" . . "the outer boundary of a black hole" . . . . . "horizons" . . "Event horizon#Cosmic event horizon" . . . "horizon" . . . "Event Horizon" . "event horizon" . "near-horizon" . . "Event horizon" . . . . . . . . "event horizons" . "circular shadow" . . . . "Event horizon" . "cosmic event horizon" .