Gamma Pyxidis, Latinized from γ Pyxidis, is a single, orange-hued star in the southern constellation

Pyxis Pyxis is a small and faint constellation in the southern sky. Abbreviated from Pyxis Nautica, its name is Latin for a mariner's compass (contrasting with Circinus, which represents a draftsman's compasses). Pyxis was introduced by Nicolas-Lo ...

. It is visible to the naked eye, having an

apparent visual magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's lig ...

of 4.010. Based upon an annual parallax shift of 15.73 mas as seen from Earth, it is located about 207 light years from the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

. The star is moving further from the Sun with a radial velocity of +24.5 km/s.

Properties

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 ...

K-type

giant star A giant star is a star with substantially larger radius and luminosity than a main-sequence (or ''dwarf'') star of the same surface temperature.Giant star, entry in ''Astronomy Encyclopedia'', ed. Patrick Moore, New York: Oxford University Press ...

with a stellar classification of K3 III. It is a

red clump Red is the color at the long wavelength end of the visible spectrum of light, next to orange and opposite violet. It has a dominant wavelength of approximately 625–740 nanometres. It is a primary color in the RGB color model and a secondary ...

star on the horizontal branch, indicating that it is generating energy through

helium fusion The triple-alpha process is a set of nuclear fusion reactions by which three helium-4 nuclei (alpha particles) are transformed into carbon. Triple-alpha process in stars Helium accumulates in the cores of stars as a result of the proton–pro ...

at its

core Core or cores may refer to: Science and technology * Core (anatomy), everything except the appendages * Core (manufacturing), used in casting and molding * Core (optical fiber), the signal-carrying portion of an optical fiber * Core, the centra ...

. The composition of the

stellar atmosphere The stellar atmosphere is the outer region of the volume of a star, lying above the stellar core, radiation zone and convection zone. Overview The stellar atmosphere is divided into several regions of distinct character: * The photosphere, whi ...

is similar to the Sun, having roughly the same abundance of iron in its

spectrum A spectrum (plural ''spectra'' or ''spectrums'') is a condition that is not limited to a specific set of values but can vary, without gaps, across a continuum. The word was first used scientifically in optics to describe the rainbow of colors ...

. The star has an estimated 1.64 times the mass of the Sun and has expanded to nearly 22 times the Sun's radius. At the age of around four billion years, it is radiating 178 times the

Sun's luminosity The solar luminosity (), is a unit of radiant flux (power emitted in the form of photons) conventionally used by astronomers to measure the luminosity of stars, galaxies and other celestial objects in terms of the output of the Sun. One nominal ...

from its enlarged photosphere at an effective temperature of 4,270 K. Gamma Pyxidis is moving through the Galaxy at a speed of 54.2 km/s relative to the Sun. Its projected Galactic orbit carries it between 21,300 and 30,700 light years from the center of the Galaxy.

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 ...

, (), meaning '' Celestial Dog'', refers to an asterism consisting of γ Pyxidis, e Velorum, f Velorum, β Pyxidis, α Pyxidis and δ Pyxidis. Consequently, γ Pyxidis itself is known as (, en, the Sixth Star of Celestial Dog.)AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 17 日
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References

{{DEFAULTSORT:Gamma Pyxidis K-type giants Horizontal-branch stars Pyxidis, Gamma Pyxis (constellation) Durchmusterung objects 075691 043409 3518