Regulus is a blue straggler star in the constellation Leo. it is the brightest star in the constellation Leo and the 21st brightest star in the night sky. The Regulus system is composed of four stars and a brown dwarf. Regulus Aa is a very oblate star, caused by its 15.9-hour rotation period. The name Regulus means ‘little king’ in Latin.
Astronomical data
Radius (in Solar Radii): 4.21 R☉
Diameter (in Kilometers): 5,860,320 km
Mass (in Solar Masses): 4.15 M☉
Distance (in Light Years): 79.1 ly
Spectral type: B8 IVn (Blue)