Tau Piscium (τ Piscium) is an orange-hued

star A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...

in the

zodiac The zodiac is a belt-shaped region of the sky that extends approximately 8° north or south (as measured in celestial latitude) of the ecliptic, the Sun path, apparent path of the Sun across the celestial sphere over the course of the year. ...

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the e ...

Pisces Pisces may refer to: * Pisces, an obsolete (because of land vertebrates) taxonomic superclass including all fish * Pisces (astrology), an astrological sign * Pisces (constellation), a constellation **Pisces Overdensity, an overdensity of stars in ...

. With an apparent visual magnitude of +4.52, it is a dim star but visible to the naked eye. Based upon an annual parallax shift of 19.32

mas Mas, Más or MAS may refer to: Film and TV * Más y Menos, fictional superhero characters, from the Teen Titans animated television series * Más (Breaking Bad), "Más" (''Breaking Bad''), a season three episode of ''Breaking Bad'' Songs * Más ( ...

as seen from Earth, it is located around 169

light year A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...

s from the Sun. It is most likely (96% chance) a member of the

thin disk The thin disk is a structural component of spiral and S0-type galaxies, composed of stars, gas and dust. It is the main non-centre (e.g. galactic bulge) density, of such matter. That of the Milky Way is thought to have a scale height of around i ...

population. This is an

evolved Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation t ...

K-type giant star with a

stellar classification In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grati ...

of K0.5 IIIb. It is about 2.27 billion years and is a red clump star on the

horizontal branch The horizontal branch (HB) is a stage of stellar evolution that immediately follows the red-giant branch in stars whose masses are similar to the Sun's. Horizontal-branch stars are powered by helium fusion in the core (via the triple-alpha process) ...

, which indicates it is generating energy through helium fusion at its core. The star has 1.7 times the

mass of the Sun The solar mass () is a standard unit of mass in astronomy, equal to approximately . It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies and black holes. It is approximately equal to the mass ...

and has expanded to about 10 times the Sun's radius. It is radiating 45 times the Sun's luminosity from its

photosphere The photosphere is a star's outer shell from which light is radiated. The term itself is derived from Ancient Greek roots, φῶς, φωτός/''phos, photos'' meaning "light" and σφαῖρα/''sphaira'' meaning "sphere", in reference to it ...

at an

effective temperature The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature ...

of 4,624 K.

Naming

Chinese Chinese can refer to: * Something related to China * Chinese people, people of Chinese nationality, citizenship, and/or ethnicity **''Zhonghua minzu'', the supra-ethnic concept of the Chinese nation ** List of ethnic groups in China, people of va ...

, (), meaning ''

Legs A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape. During locomotion, legs function as "extensible struts". The combination of movements at all joints can be modeled as a single, linear element ...

'', refers to an asterism consisting of τ Piscium,

η Andromedae Eta Andromedae (Eta And, η Andromedae, η And) is a spectroscopic binary star in the constellation of Andromeda. It consists of two G-type subgiant or giant stars orbiting each other with a period of 115.7 days an ...

, 65 Piscium,

ζ Andromedae Zeta Andromedae (Zeta And, ζ Andromedae, ζ And) is a star system in the constellation Andromeda. It is approximately 189 light-years from Earth. Zeta Andromedae is the star's Bayer designation. It also has the F ...

ε Andromedae Epsilon Andromedae, Latinized from ε Andromedae, is a star in the constellation of Andromeda. It can be seen with the naked eye, having an apparent visual magnitude of 4.4. Based upon an annual parallax shift of 21.04 ...

δ Andromedae Delta Andromedae, Latinized from δ Andromedae, is a triple star system in the northern constellation of Andromeda. The system is visible to the naked eye as a point of light with a combined apparent visual magnitude of 3.28. Based up ...

π Andromedae Pi Andromedae (Pi And, π Andromedae, π And) is the Bayer designation for a binary star system in the northern constellation of Andromeda. With an apparent visual magnitude of 4.4, it is visible to the naked eye. It i ...

ν Andromedae Nu Andromedae (Nu And, ν Andromedae, ν And) is a binary star in the constellation Andromeda. The system has an apparent visual magnitude of 4.5, which is bright enough to be seen with the naked eye. It is approximately ...

μ Andromedae Mu Andromedae (Mu And, μ Andromedae, μ And) is the Bayer designation for a star in the northern constellation of Andromeda. It has an apparent visual magnitude of 3.87, making it readily visible to the naked eye. Based ...

, β Andromedae,

σ Piscium Sigma Piscium (Sigma Psc, σ Piscium, σ Psc) is a main-sequence star in the zodiac constellation of Pisces. It has an apparent magnitude of +5.50, meaning it is barely visible to the naked eye, according to the Bortle ...

91 Piscium This is the list of notable stars in the constellation Pisces, sorted by decreasing brightness. See also *List of stars by constellation References * * * * * {{Stars of Pisces *List Pisces Pisces may refer to: * Pisces, an obsolete (beca ...

, υ Piscium,

φ Piscium Phi Piscium, Latinized from φ Piscium, is a quadruple star system approximately 380 light years away in the constellation Pisces. It consists of Phi Piscium A, with a spectral type of K0III, and Phi Piscium B. Phi Piscium A posses ...

χ Piscium Chi Piscium (χ Piscium) is a solitary, orange-hued star in the zodiac constellation of Pisces. It can be seen with the naked eye, having an apparent visual magnitude of +4.64. Based upon an annual parallax shift of 8.50 mas as ...

and ψ¹ Piscium. Consequently, the Chinese name for τ Piscium itself is (, en, the Eleventh Star of Legs.)AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日
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References

{{DEFAULTSORT:Tau Piscium K-type giants Horizontal-branch stars Piscium, Tau Pisces (constellation) Piscium, 083 Durchmusterung objects 007106 005586 0352