binary star
A binary star or binary star system is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved as separate stars us ...
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 ...
Bayer designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek alphabet, Greek or Latin letter followed by the genitive case, genitive form of its parent constellation's Latin name. The original list of Bayer design ...
that is Latinized from μ Aquarii, and abbreviated Mu Aqr or μ Aqr. The star is visible to the naked eye with a combined
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 4.7. Based upon
parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different sightline, lines of sight and is measured by the angle or half-angle of inclination between those two lines. Due to perspective (graphica ...
measurements, the distance to this system is about . It is drifting closer to 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 ...
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 −9.1 km/s.
This star was tentatively identified as a single-lined
spectroscopic binary
A binary star or binary star system is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved as separate stars us ...
orbital period
The orbital period (also revolution period) is the amount of time a given astronomical object takes to complete one orbit around another object. In astronomy, it usually applies to planets or asteroids orbiting the Sun, moons orbiting planets ...
of and an
eccentricity
Eccentricity or eccentric may refer to:
* Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal"
Mathematics, science and technology Mathematics
* Off-Centre (geometry), center, in geometry
* Eccentricity (g ...
(ovalness) of 0.23. The pair have been resolved by
speckle interferometry
Speckle imaging comprises a range of high-resolution Astrophotography, astronomical imaging techniques based on the analysis of large numbers of short Exposure (photography), exposures that freeze the variation of Astronomical seeing, atmospheri ...
, showing an
angular separation
Angular distance or angular separation is the measure of the angle between the orientation of two straight lines, rays, or vectors in three-dimensional space, or the central angle subtended by the radii through two points on a sphere. When t ...
of .
The visible
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 ...
matches 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 A3m, with the 'm' suffix indicating that this is an Am, or
chemically peculiar star
In astrophysics, chemically peculiar stars (CP stars) are stars with distinctly unusual Metallicity, metal abundances, at least in their surface layers.
Classification
Chemically peculiar stars are common among hot main-sequence (hydrogen-burning) ...
. A 2020 classification of , indicates ionized calcium (k) lines match a class of A4, hydrogen lines (h) a class of F1, and metal lines (m) F3. There are also abundance anomalies of europium (Eu) and strontium (Sr). The primary has double the mass of the Sun and 3.5 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 ...
, It is radiating 26 times the
luminosity of the Sun
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
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 6,906 K.
This star together with
ν Aquarii
Nu Aquarii is a star in the equatorial constellation of Aquarius. The name is a Bayer designation that is Latinized from ν Aquarii, and abbreviated Nu Aqr or ν Aqr. With an apparent visual magnitude of 4.52, Nu Aquarii is faintly vis ...
is
Albulaan The traditional star name Albulaan refers to two stars in the Aquarius constellation:
* μ Aquarii
* ν Aquarii
The name derives from the Arabic
Arabic (, , or , ) is a Central Semitic languages, Central Semitic language of the Afroasi ...
, derived from an
Arabic
Arabic (, , or , ) is a Central Semitic languages, Central Semitic language of the Afroasiatic languages, Afroasiatic language family spoken primarily in the Arab world. The International Organization for Standardization (ISO) assigns lang ...
term ''al-bulaʽān'' (''ألبولعان'') meaning "the two swallowers". This star, along with
ε Aqr
Epsilon Aquarii is a binary star system in the equatorial zodiac constellation of Aquarius, located near the western constellation border with Capricornus. Its identifier is a Bayer designation that is Latinized from ε Aquarii, and a ...
(Albali) and ν Aqr (Albulaan), were ''al Bulaʽ'' (''البلع''), the Swallower. In
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 ''
Girl
A girl is a young female human, usually a child or an adolescent. While the term ''girl'' has other meanings, including ''young woman'',Dictionary.com, "Girl"'' Retrieved January 2, 2008. '' daughter'' or '' girlfriend'' regardless of age ...
(asterism)'' (or ''Woman''), refers to an asterism consisting of μ Aquarii, ε Aquarii,
4 Aquarii
4 Aquarii (abbreviated 4 Aqr) is a binary star system in the constellation Aquarius, located approximately 198 light years away from the Sun. ''4 Aquarii'' is the Flamsteed designation. It is visible to the naked eye as a dim, yello ...
,
5 Aquarii
5 Aquarii is a single star in the zodiac constellation of Aquarius, located about 780 light years away from the Sun, based on parallax. ''5 Aquarii'' is the Flamsteed designation. It is visible to the naked eye as a faint, blue-white ...
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 ...
Albulaan The traditional star name Albulaan refers to two stars in the Aquarius constellation:
* μ Aquarii
* ν Aquarii
The name derives from the Arabic
Arabic (, , or , ) is a Central Semitic languages, Central Semitic language of the Afroasi ...