Beta Apodis (β Aps, β Apodis) is the
Bayer designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars. T ...
for a
star
A star is an astronomical object comprising a luminous spheroid of plasma held together by its gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night, but their immense distances from Earth make ...
in the southern
circumpolar constellation
A circumpolar star is a star that, as viewed from a given latitude on Earth, never sets below the horizon due to its apparent proximity to one of the celestial poles. Circumpolar stars are therefore visible from said location toward the nearest po ...
of
Apus
Apus is a small constellation in the southern sky. It represents a bird-of-paradise, and its name means "without feet" in Greek because the bird-of-paradise was once wrongly believed to lack feet. First depicted on a celestial globe by Petrus ...
. It is located approximately from Earth,
[ as determined by ]parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between those two lines. Due to foreshortening, nearby object ...
measurements. The 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 this star is +4.24,[ which is bright enough to be seen with the naked eye
The ]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 color ...
of this star matches the characteristics of a K0 III,[ which, according to models of ]stellar evolution
Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive, which is con ...
, indicates that it is in the 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 ...
stage, having exhausted the supply of hydrogen at its core. The measured angular diameter
The angular diameter, angular size, apparent diameter, or apparent size is an angular distance describing how large a sphere or circle appears from a given point of view. In the vision sciences, it is called the visual angle, and in optics, it i ...
of this star is .[ At the estimated distance of this star, this yields a physical size of about 11 times the ]radius of the Sun
Solar radius is a unit of distance used to express the size of stars in astronomy relative to the Sun. The solar radius is usually defined as the radius to the layer in the Sun's photosphere where the optical depth equals 2/3:
:1\,R_ = 6.9 ...
.[ The expanded outer atmosphere of Beta Apodis has 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 about 4,900 K.[ This heat is causing it to glow with the characteristic orange hue of a ]K-type star
In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting t ...
.[
]
Naming
In 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 v ...
caused by adaptation of the European southern hemisphere constellations into the Chinese system, (), meaning ''Exotic Bird
Exotic may refer to:
Mathematics and physics
* Exotic R4, a differentiable 4-manifold, homeomorphic but not diffeomorphic to the Euclidean space R4
*Exotic sphere, a differentiable ''n''-manifold, homeomorphic but not diffeomorphic to the ordinar ...
'', refers to an asterism consisting of β Apodis, ζ Apodis, ι Apodis, γ Apodis, δ Octantis, δ1 Apodis, η Apodis, α Apodis and ε Apodis. Consequently, β Apodis itself is known as (, en, the Third Star of Exotic Bird.)[AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 29 日]
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References
External links
Image Beta Apodis
{{DEFAULTSORT:Beta Apodis
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Apodis, Beta
Apus (constellation)
K-type giants
081852
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Durchmusterung objects