Upsilon Piscium Explained

Upsilon Piscium is a solitary, white-hued star in the zodiac constellation of Pisces. It is faintly visible to the naked eye, having an apparent visual magnitude of +4.75. Based upon an annual parallax shift of as seen from Earth, it is located about 308 light years from the Sun. The star is drifting further away with a heliocentric radial velocity of +6 km/s.

This is an ordinary A-type main sequence star with a stellar classification of A3 V. It is 461 million years old – about 98% of the way through its main sequence lifetime – and is spinning with a projected rotational velocity of 91 km/s. The star has 2.8 times the mass of the Sun, about 2.2 times the Sun's radius, and is radiating 117 times the Sun's luminosity from its photosphere at an effective temperature of 9183 K.

Naming

υ Piscium is the Bayer designation for this star, which is Latinized as Upsilon Piscium. It has the Flamsteed designation 90 Piscium.

In Chinese, Chinese: 奎宿 (Chinese: Kuí Sù), meaning Legs (asterism), refers to an asterism composed of υ Piscium, η Andromedae, 65 Piscium, ζ Andromedae, ε Andromedae, δ Andromedae, π Andromedae, ν Andromedae, μ Andromedae, β Andromedae, σ Piscium, τ Piscium, 91 Piscium, φ Piscium, χ Piscium and ψ¹ Piscium. Consequently, the Chinese name for υ Piscium itself is Chinese: 奎宿十三 (Chinese: Kuí Sù shí sān, English: the Thirteenth Star of Legs.)[1]

Notes and References

  1. AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日