Its high luminosity and large distance (about 1,500 light years) give it an apparent visible magnitude of 5.1.

Theta1 C is itself a binary of two massive stars, C1 and C2, plus a very close fainter companion apparently escaping the system.

[9] Theta1 Orionis C1 is responsible for generating most of the ultraviolet light that is slowly ionizing (and perhaps photoevaporating) the Orion Nebula.

The star emits a powerful stellar wind that is a hundred thousand times stronger than the Sun's, and the outpouring gas moves at 1,000 km/s.

This field is confining the motion of the strong stellar wind, which should reduce the mass loss rate by 80%.