Mu Piscis Austrini
# Mu Piscis Austrini

Mu Piscis Austrini, Latinized from μ Piscis Austrini, is a solitary, white-hued star in the southern constellation of Piscis Austrinus. It is visible to the naked eye with an apparent visual magnitude of +4.49. Based upon an annual parallax shift of 26.75 mas as seen from the Gaia space telescope, the star is located around 122±2 light years from the Sun.

This star has the spectrum of an A-type subgiant with a stellar classification of A1.5 IVn. It is spinning rapidly with a projected rotational velocity of 308 km/s. This is giving the star an oblate shape with an equatorial bulge that is an estimated 23% larger than the polar radius. An X-ray emission has been detected from this star with a luminosity of $89.6×10^{27}$ erg $s^{−1}.$ This may be coming from an undiscovered companion, since A-type stars are not expected to be a significant source of X-rays.

Mu Piscis Austrini is moving through the Galaxy at a speed of 20 km/s relative to the Sun. Its projected Galactic orbit carries it between 23,800 and 28,500 light years from the center of the Galaxy. Mu Piscis Austrini came closest to the Sun 1.2 million years ago at a distance of 111 light years.

## Naming

In Chinese, 天錢 (Tiān Qián), meaning Celestial Money, refers to an asterism consisting of refers to an asterism consisting of μ Piscis Austrini, 13 Piscis Austrini, θ Piscis Austrini, ι Piscis Austrini and τ Piscis Austrini. Consequently, the Chinese name for μ Piscis Austrini itself is 天錢四 (Tiān Qián sì, English: the Fifth Star of Celestial Money.)

