Alpha Trianguli
Encyclopedia
Alpha Trianguli is a binary star
Binary star
A binary star is a star system consisting of two stars orbiting around their common center of mass. The brighter star is called the primary and the other is its companion star, comes, or secondary...

 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....

 Triangulum
Triangulum
Triangulum is a small constellation in the northern sky. Its name is Latin for triangle, and it should not be confused with Triangulum Australe in the southern sky. Its name derives from its three brightest stars, of third and fourth magnitude, which form a nearly isosceles long and narrow triangle...

. It has the traditional names Mothallah or Ras al Muthallah (alternate spellings Mathallah, Metallah, Ras al Mothallah, Elmuthalleth), and Caput Trianguli, from the Arabic رأس المثلث ra’s al-muθallaθ "the head of the triangle" and its Latin translation.

Alpha Trianguli is a yellow-white F-type
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...

 subgiant with a mean apparent magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...

 of +3.41. Its mass is about 1.5 times that of the Sun and its diameter is about 3 times as large as the Sun's.

Mothallah is a spectroscopic binary whose components have an orbital period of only 1.74 days. The companion star is a mere 6 million km (3.7 million miles) from the main star. The whole system is approximately 64.1 light years
Light Years
Light Years is the seventh studio album by Australian recording artist Kylie Minogue. It was released on 25 September 2000 by Parlophone and Mushroom Records. The album's style was indicative of her return to "mainstream pop dance tunes"....

 from Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

.

α Tri is listed as UR.BAR.RA "The Wolf", bearing the epithet "the seeder of the plough" in the MUL.APIN
MUL.APIN
MUL.APIN is the conventional title given to a Babylonian compendium that deals with many diverse aspects of Babylonian astronomy and astrology....

, listed after "The Plough", the name for a constellation formed of Triangulum
Triangulum
Triangulum is a small constellation in the northern sky. Its name is Latin for triangle, and it should not be confused with Triangulum Australe in the southern sky. Its name derives from its three brightest stars, of third and fourth magnitude, which form a nearly isosceles long and narrow triangle...

 plus Gamma Andromedae
Gamma Andromedae
Gamma Andromedae is the third brightest star in the constellation of Andromeda. It is also known by the traditional name Almach , from the Arabic العناق الأرض al-‘anāq al-’arđ̧ "the caracal" .Another term for this star used by medieval astronomers...

.

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