Nu Andromedae


Nu Andromedae is a binary star system in the constellation Andromeda. Its Bayer designation is Latinized from ν Andromedae, and abbreviated Nu And or ν And, respectively. The system has an apparent visual magnitude of 4.5, which is bright enough to be seen with the naked eye. Based on parallax measurements, it is located at a distance of approximately from Earth. The pair are drifting closer with a heliocentric radial velocity of –24 km/s. Situated just over a degree to the west of this star is the Andromeda Galaxy.
Nu Andromedae is close spectroscopic binary system with a period of 4.2828 days and a nearly circular orbit. The primary component is a B-type main sequence star with a stellar classification of B5 V. The fainter secondary has a classification of F8 V, which makes it an F-type main sequence star. The pair is about 63 million years old.
The pair have a peculiar velocity of relative to neighboring stars, which doesn't qualify it to be a runaway star system but does suggest it escaped its star cluster of origin. The trajectory indicates it may have left the NGC 6405 cluster some 25 million years ago.

Naming

In Chinese, 奎宿, meaning Legs , refers to an asterism consisting of ν Andromedae, η Andromedae, 65 Piscium, ζ Andromedae, ε Andromedae, δ Andromedae, π 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 ν Andromedae itself is 奎宿七