Gamma Boötis
Encyclopedia
Gamma Boötis is a star
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...

 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....

 Boötes
Boötes
Boötes is a constellation in the northern sky, located between 0° and +60° declination, and 13 and 16 hours of right ascension on the celestial sphere. The name comes from the Greek Βοώτης, Boōtēs, meaning herdsman or plowman...

. It has the traditional name Seginus (also Segin, Ceginus) of uncertain origin. It was listed as Haris in Bečvář
Antonín Bečvář
Antonín Bečvář was a Czech astronomer who was active in Slovakia. He was born in Stará Boleslav. Among his chief achievements is the foundation of the Skalnaté Pleso Observatory and the discovery of the comet C/1947 F2 .Bečvář is particularly important for his star charts: he led the compilation...

.

In Chinese astronomy
Chinese astronomy
Astronomy in China has a very long history, with historians considering that "they [the Chinese] were the most persistent and accurate observers of celestial phenomena anywhere in the world before the Arabs."...

, Seginus is called 招搖, Pinyin
Pinyin
Pinyin is the official system to transcribe Chinese characters into the Roman alphabet in China, Malaysia, Singapore and Taiwan. It is also often used to teach Mandarin Chinese and spell Chinese names in foreign publications and used as an input method to enter Chinese characters into...

: Zhāoyáo, meaning Twinkling Indicator, because this star is marking itself and stand alone in Twinkling Indicator asterism, Root
Root (Chinese constellation)
The Root mansion is one of the Twenty-eight mansions of the Chinese constellations. It is one of the eastern mansions of the Azure Dragon.-Asterisms:...

 mansion (see : Chinese constellation
Chinese constellation
Chinese constellations are the way the ancient Chinese grouped the stars. They are very different from the modern IAU recognized constellations. This is because the IAU was based on Greco-Roman astronomy instead of Chinese astronomy....

). 招搖 (Zhāoyáo), westernized into Chaou Yaou, but the name Chaou Yaou was designated for β Boötis
Beta Boötis
Beta Boötis is a variable star in the constellation Boötes. It is a yellow G-type giant with an apparent magnitude of +3.49. The traditional name Nakkar or Nekkar is based upon the Arabic name for the constellation...

 (Nekkar) by R.H. Allen and the meaning is "to beckon, excite, or move."

In the catalogue of stars in the Calendarium of Al Achsasi al Mouakket
Al Achsasi al Mouakket
Mohammad Al Achsasi Al Mouakket was an Egyptian astronomer whose calendarium and catalogue of stars, entitled Durret al Muddiah Fih al Aamal al Shamsiah , was written at Cairo about 1650.Al Achsasi was sheikh of the Grand Mosque of the University of Cairo, where his name al...

, this star was designated Menkib al Aoua al Aisr (منكب العواء الأيسر - mankibu lʿawwaaʾi lʾaysar), 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 Humerus Sinister Latratoris, meaning the left shoulder of barker.

The name Seginus resulted from Latinization of an Arabic
Arabic language
Arabic is a name applied to the descendants of the Classical Arabic language of the 6th century AD, used most prominently in the Quran, the Islamic Holy Book...

 form of the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

 name of 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 Boötes
Boötes
Boötes is a constellation in the northern sky, located between 0° and +60° declination, and 13 and 16 hours of right ascension on the celestial sphere. The name comes from the Greek Βοώτης, Boōtēs, meaning herdsman or plowman...

 (Theguius). The name Haris comes from the Arabic name of the constellation of Boötes, Al Haris Al Sama, which means "the guard".

Structure

Gamma Boötis is approximately 85 light years away from Earth. It belongs to the spectral class
Stellar classification
In astronomy, stellar classification is a classification of stars based on their spectral characteristics. The spectral class of a star is a designated class of a star describing the ionization of its chromosphere, what atomic excitations are most prominent in the light, giving an objective measure...

 A7III. It is a Delta Scuti type
Delta Scuti variable
A Delta Scuti variable is a variable star which exhibits variations in its luminosity due to both radial and non-radial pulsations of the star's surface. Typical brightness fluctuations are from 0.003 to 0.9 magnitudes in V over a period of a few hours, although the amplitude and period of the...

 variable star
Variable star
A star is classified as variable if its apparent magnitude as seen from Earth changes over time, whether the changes are due to variations in the star's actual luminosity, or to variations in the amount of the star's light that is blocked from reaching Earth...

 and its brightness varies from magnitude +3.02 to +3.07 with a period of 6.97 hours.

Namesakes

USS Seginus (AK-133)
USS Seginus (AK-133)
USS Seginus was an commissioned by the U.S. Navy for service in World War II. She was responsible for delivering troops, goods and equipment to locations in the war zone....

 was a United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...

 Crater class cargo ship
Crater class cargo ship
Crater-class cargo ship is a category of freighter that was constructed for use by the United States Navy during World War II under Maritime Commission EC2-S-C1 type....

named after the star.
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