Magnitude 4.88 Apparent magnitude (V) 4.88 | Constellation Cassiopeia | |
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Similar Tau Cassiopeiae, Psi Cassiopeiae, Iota Cassiopeiae, Lambda Cassiopeiae, Omicron Cassiopeiae | ||
Sigma Cassiopeiae (σ Cas, σ Cassiopeiae) is a binary star in the constellation Cassiopeia. It is approximately 5000 light years from Earth and has a combined apparent magnitude of +4.88.
The primary component, σ Cassiopeiae A, is a B2 subgiant with an apparent magnitude of +5.0. Its companion, σ Cassiopeiae B, is a B5 main sequence dwarf with an apparent magnitude of +7.1. The two stars are three arcseconds apart.
Naming
In Chinese, 螣蛇 (Téng Shé), meaning Flying Serpent, refers to an asterism consisting of σ Cassiopeiae, α Lacertae, 4 Lacertae, π2 Cygni, π1 Cygni, HD 206267, ε Cephei, β Lacertae, ρ Cassiopeiae, τ Cassiopeiae, AR Cassiopeiae, 9 Lacertae, 3 Andromedae, 7 Andromedae, 8 Andromedae, λ Andromedae, κ Andromedae, ι Andromedae, and ψ Andromedae. Consequently, σ Cassiopeiae itself is known as 螣蛇十一 (Téng Shé shíyī, English: the Eleventh Star of Flying Serpent).