Pi Andromedae


Pi Andromedae is a binary star system in the northern constellation of Andromeda. Its Bayer designation is latinized from π Andromedae, and abbreviated Pi And or π And, respectively. With an apparent visual magnitude of 4.4, it is visible to the naked eye. Based on parallax measurements, it is located at a distance of approximately from Earth.
Image:Pi Andromedae.jpg|thumb|left|π Andromedae in optical light
The pair is classified as a blue-white B-type main sequence dwarf, with an apparent magnitude of +4.34. It is a spectroscopic binary with an orbital period of 143.5 days and an eccentricity of 0.54.
The spectroscopic binary forms a triple system with BD+32 102, a magnitude 8.6 star located 35.9 arcseconds away. At 55 arcseconds separation is an 11th magnitude companion that is just located on the same line of sight, but at a very different distance from us.

Naming

In Chinese, 奎宿, meaning Legs , refers to an asterism consisting of π Andromedae, η Andromedae, 65 Piscium, ζ Andromedae, ε Andromedae, δ Andromedae, ν Andromedae, μ Andromedae, β Andromedae, σ Piscium, τ Piscium, 91 Piscium, υ Piscium, φ Piscium, χ Piscium and ψ¹ Piscium. Consequently, the Chinese name for π Andromedae itself is 奎宿六