Lambda Cassiopeiae

Lambda Cassiopeiae (λ Cas, λ Cassiopeiae) is a binary star in the constellation Cassiopeia. The system has a combined apparent magnitude of +4.74 and is approximately 380 light years from Earth.

Both components are blue-white B-type main sequence dwarfs. The brighter, λ Cassiopeiae A, has an apparent magnitude of +5.5, while its companion, λ Cassiopeiae B, has an apparent magnitude of +5.8. The two stars are separated by 0.6 arcseconds and complete one orbit around their common centre of mass once every 640 years.