Suhail al Muhlif

Regor (also called Suhail al Muhlif) is one of the most remarkable star systems visible to the naked eye at magnitude 1.78. The primary is a Wolf-Rayet star (spectral type WC8) in a binary with an O9 supergiant, located about 1,100 light-years away. Wolf-Rayet stars are extremely hot, massive stars that are blowing off their outer layers in powerful stellar winds at thousands of km/s, exposing their helium-burning cores.

Gamma Vel lies in the rich Milky Way fields of Vela and is one of the finest wide double stars in the sky — a small telescope reveals a brilliant pair of blue-white stars separated by about 41 arcseconds. The surrounding star field is gorgeous in binoculars. Visible from the southern hemisphere and low northern latitudes. Best observed February through May.

The informal name Regor (Roger spelled backwards) was a joke by Apollo 1 astronaut Gus Grissom, honoring crewmate Roger Chaffee. The name stuck in some usage. Gamma Vel was one of the first Wolf-Rayet stars identified, and its extreme spectral features have made it a prototype for studying massive stellar evolution.