Beta Sagittae, Latinized from β Sagittae, is a single

star A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

in the northern

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 first constellati ...

Sagitta Sagitta is a dim but distinctive constellation in the northern sky. Its name is Latin for 'arrow', not to be confused with the significantly larger constellation Sagittarius 'the archer'. It was included among the 48 constellations listed by t ...

. It is a faint star but visible to the naked eye with an

apparent visual magnitude Apparent magnitude () is a measure of the brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction of the object's light ca ...

of 4.38. Based upon an annual parallax shift of 7.7237

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''), a season three episode of ''Breaking Bad'' Music Albums * ''Más'' (album), ...

as seen from the Gaia satellite, it is located 420

light year A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distance, astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by t ...

s from the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

. The star is moving closer to the Sun with a

radial velocity The radial velocity or line-of-sight velocity of a target with respect to an observer is the rate of change of the vector displacement between the two points. It is formulated as the vector projection of the target-observer relative velocity ...

of −22 km/s. This is an

evolved Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

red giant A red giant is a luminous giant star of low or intermediate mass (roughly 0.3–8 solar masses ()) in a late phase of stellar evolution. The stellar atmosphere, outer atmosphere is inflated and tenuous, making the radius large and the surface t ...

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 gratin ...

of . The suffix notation indicates a mild overabundance of the

cyanogen Cyanogen is the chemical compound with the chemical formula, formula . Its structure is . The simplest stable carbon nitride, it is a Transparency and translucency, colorless and highly toxic gas with a pungency, pungent odor. The molecule is a ...

molecule in the

spectrum A spectrum (: spectra or spectrums) is a set of related ideas, objects, or properties whose features overlap such that they blend to form a continuum. The word ''spectrum'' was first used scientifically in optics to describe the rainbow of co ...

. Beta Sagittae is an estimated 129 million years old with 3.755 times the

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

, and has expanded to 25.7 times the

Sun's radius Solar radius is a unit of distance used to express the size of objects 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_ = 6.957\ti ...

. The star is radiating 369 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 s ...

from its enlarged

photosphere The photosphere is a star's outer shell from which light is radiated. It extends into a star's surface until the plasma becomes opaque, equivalent to an optical depth of approximately , or equivalently, a depth from which 50% of light will esc ...

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 4,990 K.

Naming

Chinese Chinese may refer to: * Something related to China * Chinese people, people identified with China, through nationality, citizenship, and/or ethnicity **Han Chinese, East Asian ethnic group native to China. **'' Zhonghua minzu'', the supra-ethnic ...

, (), meaning '' Left Flag'', refers to an asterism consisting of β Sagittae, α Sagittae, δ Sagittae,

ζ Sagittae Zeta Sagittae (ζ Sagittae) is triple star system in the northern constellation of Sagitta. It is visible to the naked eye, having a combined apparent visual magnitude of +5.00. Based upon an annual parallax shift of , the distance ...

, γ Sagittae,

13 Sagittae 13 Sagittae is a single star in the northern constellation of Sagitta. The designation comes from the star catalogue of John Flamsteed, first published in 1712. It can be viewed with the naked eye, having an apparent visual magnitude vary ...

11 Sagittae 11 Sagittae is a blue giant in the constellation Sagitta with a spectral type of B9III. Naming It is in the Chinese asterism (), or '' Left Flag'' which consists of 11 Sagittae, γ Sagittae, α Sagittae, β Sagittae, δ Sagittae, ζ ...

14 Sagittae 14 Sagittae is a binary star system in the equatorial constellation of Aquila. ''14 Sagittae'' is the Flamsteed designation. It appears as a sixth magnitude star, near the lower limit of visibility to the naked eye, having an apparent vis ...

and ρ Aquilae. Consequently, the

Chinese name Chinese may refer to: * Something related to China * Chinese people, people identified with China, through nationality, citizenship, and/or ethnicity **Han Chinese, East Asian ethnic group native to China. **'' Zhonghua minzu'', the supra-ethni ...

for β Sagittae itself is (, .)AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 3 日

References

{{DEFAULTSORT:Beta Sagittae G-type giants Sagitta Sagittae, Beta Durchmusterung objects Sagittae, 06 185958 096837 7488