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Pollux (star)
Encyclopedia
Pollux is an orange giant star
approximately 34 light-year
s from the Earth in the constellation
of Gemini
(the Twins
). Pollux is the brightest star in the constellation, brighter than Castor
(Alpha Geminorum). In 2006, Pollux was confirmed to have an extrasolar planet
orbiting it, making it the brightest star in the sky with a known planet, other than the Sun.
, the sons of Leda
. The star also bears Arabic name Al-Ras al-Tau'am al-Mu'akhar,(الرأس التؤام المؤخر), literally, 'The Head of the Second Twin.' Castor and Pollux together correspond to the Nakshatra
Punarvasu
in Hindu
astronomy
.
Castor and Pollux are the two 'heavenly twin' stars giving the constellation Gemini (Latin, 'the twins') its name. The stars, however, are quite different in detail. Castor is a complex sextuple system of hot, bluish-white A-type stars and dim red dwarfs, while Pollux is a single, cooler yellow-orange giant
.
In the catalogue of stars in the Calendarium of Al Achsasi Al Mouakket, this star was designated Muekher al Dzira, which was translated into Latin
as Posterior Brachii, meaning the end in the paw.
In Chinese
, , meaning North River
, refers to an asterism consisting of Pollux, ρ Geminorum and Castor
. Consequently, Pollux itself is known as
Pollux b
was finally detected. Pollux b has been calculated to have a minimum mass of 2.3 times that of Jupiter
. Pollux b is currently one of the few known exoplanets to be orbiting a star that is visible to the naked eye.
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
approximately 34 light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s from the Earth in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
of Gemini
Gemini (constellation)
Gemini is one of the constellations of the zodiac. It was one of the 48 constellations described by the 2nd century astronomer Ptolemy and it remains one of the 88 modern constellations today. Its name is Latin for "twins", and it is associated with the twins Castor and Pollux in Greek mythology...
(the Twins
TWINS
Two Wide-Angle Imaging Neutral-Atom Spectrometers are a pair of NASA instruments aboard two United States National Reconnaissance Office satellites in Molniya orbits. TWINS was designed to provide stereo images of the Earth's ring current. The first instrument, TWINS-1, was launched aboard USA-184...
). Pollux is the brightest star in the constellation, brighter than Castor
Castor (star)
Castor is the second brightest star in the constellation Gemini and one of the brightest stars in the night sky. Although it has the Bayer designation "alpha", it is actually fainter than Beta Geminorum...
(Alpha Geminorum). In 2006, Pollux was confirmed to have an extrasolar planet
Extrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...
orbiting it, making it the brightest star in the sky with a known planet, other than the Sun.
Naming
The name Pollux refers specifically to Castor and PolluxCastor and Pollux
In Greek and Roman mythology, Castor and Pollux or Polydeuces were twin brothers, together known as the Dioscuri . Their mother was Leda, but Castor was the mortal son of Tyndareus, king of Sparta, and Pollux the divine son of Zeus, who visited Leda in the guise of a swan...
, the sons of Leda
Leda (mythology)
In Greek mythology, Leda was daughter of the Aetolian king Thestius, and wife of the king Tyndareus , of Sparta. Her myth gave rise to the popular motif in Renaissance and later art of Leda and the Swan...
. The star also bears Arabic name Al-Ras al-Tau'am al-Mu'akhar,(الرأس التؤام المؤخر), literally, 'The Head of the Second Twin.' Castor and Pollux together correspond to the Nakshatra
Nakshatra
Nakshatra is the term for lunar mansion in Hindu astrology. A nakshatra is one of 27 sectors along the ecliptic...
Punarvasu
Punarvasu
Punarvasu is a Nakshatra in Hindu astrology, which refers to the two brightest stars in the constellation of Gemini: Castor and Pollux.In Malayalam Punarvasu is termed Punartham...
in Hindu
Hindu
Hindu refers to an identity associated with the philosophical, religious and cultural systems that are indigenous to the Indian subcontinent. As used in the Constitution of India, the word "Hindu" is also attributed to all persons professing any Indian religion...
astronomy
Hindu calendar
The hindu calendar used in ancient times has undergone many changes in the process of regionalization, and today there are several regional Indian calendars, as well as an Indian national calendar. Nepali calendar, Bengali calendar, Malayalam calendar, Tamil calendar, Telugu calendar, Kannada...
.
Castor and Pollux are the two 'heavenly twin' stars giving the constellation Gemini (Latin, 'the twins') its name. The stars, however, are quite different in detail. Castor is a complex sextuple system of hot, bluish-white A-type stars and dim red dwarfs, while Pollux is a single, cooler yellow-orange giant
Giant star
A giant star is a star with substantially larger radius and luminosity than a main sequence star of the same surface temperature. Typically, giant stars have radii between 10 and 100 solar radii and luminosities between 10 and 1,000 times that of the Sun. Stars still more luminous than giants are...
.
In the catalogue of stars in the Calendarium of Al Achsasi Al Mouakket, this star was designated Muekher al Dzira, which was translated into Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
as Posterior Brachii, meaning the end in the paw.
In Chinese
Chinese language
The Chinese language is a language or language family consisting of varieties which are mutually intelligible to varying degrees. Originally the indigenous languages spoken by the Han Chinese in China, it forms one of the branches of Sino-Tibetan family of languages...
, , meaning North River
Well (Chinese constellation)
The Well mansion is one of the Twenty-eight mansions of the Chinese constellations. It is one of the southern mansions of the Vermilion Bird.-Asterisms:...
, refers to an asterism consisting of Pollux, ρ Geminorum and Castor
Castor (star)
Castor is the second brightest star in the constellation Gemini and one of the brightest stars in the night sky. Although it has the Bayer designation "alpha", it is actually fainter than Beta Geminorum...
. Consequently, Pollux itself is known as
Planetary system
Announced on June 16, 2006, a suspected extrasolar planetExtrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...
Pollux b
Pollux b
Pollux b, also known as Beta Geminorum b and HD 62509 b, is an extrasolar planet approximately 34 light-years away in the constellation of Gemini . This planet was discovered orbiting the star Pollux in 2006. The planet has a comparable mass to the gas giants in our solar system...
was finally detected. Pollux b has been calculated to have a minimum mass of 2.3 times that of Jupiter
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...
. Pollux b is currently one of the few known exoplanets to be orbiting a star that is visible to the naked eye.
See also
- AldebaranAldebaranAldebaran is a red giant star located about 65 light years away in the zodiac constellation of Taurus. With an average apparent magnitude of 0.87 it is the brightest star in the constellation and is one of the brightest stars in the nighttime sky...
- Castor (star)Castor (star)Castor is the second brightest star in the constellation Gemini and one of the brightest stars in the night sky. Although it has the Bayer designation "alpha", it is actually fainter than Beta Geminorum...
- Pollux in fiction