Sig

Its story

Sigma Orionis presides over a young cluster of several hundred forming stars, just southeast of Orion's Belt and a stone's throw from the Horsehead Nebula it helps to backlight. Its primary is one of the rare O-type stars within naked-eye reach—a hot blue lantern marshalling a swarm of still-young suns around it. The light crosses more than a thousand years before it reaches the eye.