Tags: Star.
Sigma Orionis or Sigma Ori (σ Orionis σ Ori) is a five-star system in the constellation Orion just to the southwest of Alnitak. It is approximately 1150 light years from Earth.The primary component is the binary Sigma Orionis AB with the two stars being a mere 0.25 arcseconds apart. Both stars are hydrogen-fusing dwarfs only a few million years old. The brighter one Sigma Orionis A is a blue O-type star with an apparent visual magnitude of +4.2.
