Delta Arietis (δ Arietis, abbreviated Delta Ari, δ Ari), officially named Botein , is 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

northern Northern may refer to the following: Geography * North, a point in direction * Northern Europe, the northern part or region of Europe * Northern Highland, a region of Wisconsin, United States * Northern Province, Sri Lanka * Northern Range, a ...

constellation of

Aries Aries may refer to: *Aries (astrology), an astrological sign *Aries (constellation), a constellation of stars in the zodiac Arts, entertainment and media * ''Aries'' (album), by Luis Miguel, 1993 * ''Aries'' (EP), by Alice Chater, 2020 * "Aries" ...

, 1.8 degrees north of the ecliptic. 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 ...

is 4.35, so it is visible to the naked eye. It has an annual

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 ...

shift of 19.22

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'' Songs * ''Más'' (album), by Span ...

; corresponding to a distance of about 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 rad ...

Nomenclature

''δ Arietis'' ( Latinised to ''Delta Arietis'') is the star's

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 ...

. It bore the traditional name ''Botein'' which is derived from Al Bīrūnī's ''Al Buṭayn'' (

Arabic Arabic (, ' ; , ' or ) is a Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C. E.Watson; Walte ...

: البُطَين), the diminutive of ''Al Baṭn'', "the Belly". This is the name of a star association consisting of this star, Epsilon Arietis,

Zeta Arietis Zeta Arietis, Latinized from ζ Arietis, is the Bayer designation for a star in the northern constellation of Aries. It is dimly visible to the naked eye with an apparent visual magnitude of +4.89. Based upon an annual parallax shift of ...

Pi Arietis Pi Arietis, Latinized from π Arietis, is the Bayer designation for a multiple star system in the northern constellation of Aries. Based upon parallax measurements made during the Hipparcos mission, this system is approximately distant ...

, and Rho³ Arietis According to a 1971

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedi ...

catalogue of stars, ''Al Buṭain'' was the title for five stars: Delta Arietis (listed as ''Botein''), Pi Arietis (as ''Al Buṭain I''), Rho3 Arietis (''Al Buṭain II''), Epsilon Arietis (''Al Buṭain III'') and Zeta Arietis (''Al Buṭain IV''). In 2016, the

International Astronomical Union The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach ...

organized a

Working Group on Star Names The International Astronomical Union (IAU) established a Working Group on Star Names (WGSN) in May 2016 to catalog and standardize List of proper names of stars, proper names for stars for the international astronomical community. It operates under ...

(WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name ''Botein'' for this star on 12 September 2016 and it is now so included in the List of IAU-approved Star Names. In the catalogue of stars in the ''Calendarium of Al Achsasi Al Mouakket'', this star was designated ''Nir al Botain'', which was translated into

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

as ''Lucida Ventris'', meaning "the brightest of the belly". 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 ...

, (), meaning '' Yin Force'', refers to an asterism consisting of Delta Arietis,

63 Arietis Tau2 Arietis, Latinized from τ2 Arietis, is the Bayer designation for a binary star in the northern constellation on Aries. The combined apparent visual magnitude of this system is +5.09, which is bright enough to be seen with the nak ...

, Zeta Arietis, Tau Arietis and

65 Arietis 65 Arietis is a star in the northern constellation of Aries, located near Tau Arietis. ''65 Arietis'', abbreviated '65 Ari', is the Flamsteed designation. It has an apparent visual magnitude of 6.07, which, according to the Bortle Dark-S ...

. Consequently, the

Chinese name Chinese names or Chinese personal names are names used by individuals from Greater China and other parts of the Chinese-speaking world throughout East and Southeast Asia (ESEA). In addition, many names used in Japan, Korea and Vietnam are oft ...

for Delta Arietis itself is (, en, the Fourth Star of Yin Force.)香港太空館 - 研究資源 - 亮星中英對照表
, Hong Kong Space Museum. Accessed on line November 23, 2010.

Properties

Delta Arietis 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 te ...

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 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 ...

of K2 III. It belongs to a population known as

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 seconda ...

giants, which means it is generating energy through the fusion of helium at its core. With close to twice 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 of ...

, the outer envelope has expanded until it is around ten times the Sun's radius. It shines with 45 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 nomi ...

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 4,810 K, giving it the orange-hued glow 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 ...

. It is a suspected

variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as e ...

that ranges in magnitude from 4.33 to 4.37.

References

External links

HR 951

Image Delta Arietis
{{DEFAULTSORT:Delta Arietis Aries (constellation) K-type giants Horizontal-branch stars

Botein Delta Arietis (δ Arietis, abbreviated Delta Ari, δ Ari), officially named Botein , is a star in the northern constellation of Aries, 1.8 degrees north of the ecliptic. The apparent visual magnitude is 4.35, so it is visible to the nak ...

Arietis, Delta Arietis, 57 0951 019787 BD+19 0477 014838