Beta Lacertae, also named Alsamaka, is the fourth-brightest star in the constellation of Lacerta. Based upon an annual parallax shift of 19.19 mas, it is 170 light-years distant from Earth. At that distance, the visual magnitude is diminished by an extinction factor of 0.17 due to interstellar dust.
This is an evolved G-type giant with an apparent visual magnitude of approximately 4.43. It is a red clump star and the primary component of a suspected binary system, with the pair having an angular separation of 0.2 arcsecond.
Nomenclature Beta Lacertae (Latinized from β Lacertae, abbreviated Beta Lac, β Lac) is the star's Bayer designation. It was part of the Arabic asterism Al-Samaka al-Ṣuġrā ( "the smaller fish") in Lacerta and Andromeda. The IAU Working Group on Star Names adopted the name Alsamaka ( "the fish") for this star on 13 August 2026.
In Chinese astronomy, (), meaning Flying Serpent, refers to an asterism consisting of β Lacertae, α Lacertae, 4 Lacertae, π2 Cygni, π1 Cygni, HD 206267, ε Cephei, σ Cassiopeiae, ρ Cassiopeiae, τ Cassiopeiae, AR Cassiopeiae, 9 Lacertae, 3 Andromedae, 7 Andromedae, 8 Andromedae, λ Andromedae, κ Andromedae, ι Andromedae and ψ Andromedae. Consequently, the Chinese name for β Lacertae itself is (, ). AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 7 日
References Vizier catalog entry