Alpha Equulei (α Equulei, abbreviated Alpha Equ, α Equ), officially named Kitalpha ,
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
constellation of
Equuleus
Equuleus ( ) is a constellation of stars that are visible in the night sky. Its name is Latin for "little horse", a foal. Located just north of the celestial equator, it was one of the 48 constellations listed by the 2nd century astronomer Ptol ...
. It is a high
proper-motion
Proper motion is the astrometric measure of the observed changes in the apparent places of stars or other celestial objects in the sky, as seen from the center of mass of the Solar System, compared to the abstract background of the more dista ...
star only 190
light-year
A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 101 ...
s away.
Nomenclature
''α Equulei'' (
Latinised to ''Alpha Equulei'') 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 ''Kitalpha'' (rarely ''Kitel Phard'' or ''Kitalphar)'', a contraction of the
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 ...
name قطعة الفرس ''qiṭ‘a(t) al-faras''—"a piece of the horse". 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 ''Kitalpha'' for this star on 21 August 2016 and it is now so entered in the IAU Catalog of Star Names.
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
Emptiness
Emptiness as a human condition is a sense of generalized boredom, social alienation and apathy. Feelings of emptiness often accompany dysthymia, depression, loneliness, anhedonia,
despair, or other mental/emotional disorders, including schiz ...
, is an
asterism consisting of Alpha Equulei and
Beta Aquarii. 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 Alpha Equulei itself is (, en, the Second Star of Emptiness).
Properties
The overall appearance of α Equulei is a
G-type
Gaea
Gaea is one of the Elder Gods of Earth.
Gaia
Gaia, also known as the Guardian of the Universal Amalgamator, is a fictional superhero, depicted as possibly being a mutant or extraterrestrial. Created by Larry Hama, she first appeared in ...
giant
In folklore, giants (from Ancient Greek: '' gigas'', cognate giga-) are beings of human-like appearance, but are at times prodigious in size and strength or bear an otherwise notable appearance. The word ''giant'' is first attested in 1297 fr ...
with an
apparent 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 li ...
of +3.92, but it is a
spectroscopic binary consisting of two individual stars.
The primary star is a G7 giant about fifty times more
luminous than the Sun. It has an effective temperature of and a
radius
In classical geometry, a radius ( : radii) of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length. The name comes from the latin ''radius'', meaning ray but also the ...
of 9.2 times greater than the Sun.
The secondary is an
A-type dwarf
Dwarf or dwarves may refer to:
Common uses
*Dwarf (folklore), a being from Germanic mythology and folklore
* Dwarf, a person or animal with dwarfism
Arts, entertainment, and media Fictional entities
* Dwarf (''Dungeons & Dragons''), a humanoid ...
about 26 times as luminous as the sun. It has an effective temperature of 8,150 K and a radius 2.6 times greater than the sun. It is a
chemically peculiar
In astrophysics, chemically peculiar stars (CP stars) are stars with distinctly unusual metal abundances, at least in their surface layers.
Classification
Chemically peculiar stars are common among hot main-sequence (hydrogen-burning) stars. Thes ...
Am star An Am star or metallic-line star is a type of chemically peculiar star of spectral type A whose spectrum has strong and often variable absorption lines of metals such as zinc, strontium, zirconium, and barium, and deficiencies of others, such as c ...
.
[
The two stars revolve in a circular orbit every 98.8 days. Their respective orbital velocities allow their masses to be calculated at and , respectively.][
]
References
{{DEFAULTSORT:Alpha Equulei
Equulei, Alpha
Equuleus
G-type giants
A-type main-sequence stars
Spectroscopic binaries
Kitalpha
104987
Equulei, 08
8131
202447
BD+04 4635