One of the distinguishing features of the Orion constellation are the three stars which form the "belt" across the middle of Orion:  Alnitak, Alnilam and Mintaka. In the classic episode from the original series of Star Trek, "The City on the Edge of Forever", James T. Kirk pointed out Alnitak in the night sky to Judith Keeler, talking about a writer who came from "a planet circling the far left star in Orion's Belt". 

The name Alnitak (or Zeta Orionis) is taken from the Arabic an-nitaq, "the belt". Alnitak is a triple star system at the eastern end of Orion's belt. The primary is a blue supergiant that is also a close binary and its companion  is a dull red. Close by, just to the south, is the renowned Horsehead Nebula, a so-called dark nebula that is not visible in scopes but quite spectacular in long-exposure photographs.









Orion's Belt