Mu Ursae Majoris
Mu Ursae Majoris is a 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
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....

 Ursa Major
Ursa Major
Ursa Major , also known as the Great Bear, is a constellation visible throughout the year in most of the northern hemisphere. It can best be seen in April...

. It also has the proper names Tania Australis (former Tania australis) meaning "the Southern (star) of Tania." The word Tania comes from the Arabic phrase (al-Qafzah) al-Thāniyah meaning "the Second (Leap)" (the distinctions "southern" (australis) is added in Latin), Alkafzah Borealis, and El Phekrah comes from the Arabic phrase al-Fiqrah (al-Thāniyah) meaning "(the Second) Vertebra". With Lambda Ursae Majoris
Lambda Ursae Majoris
Lambda Ursae Majoris is a star in the constellation Ursa Major. It also has the proper names Tania Borealis meaning "the Northern of Tania." The word Tania comes from the Arabic phrase al-Thāniyah meaning "the Second " , and Alkafzah...

, they were Chung Tae (中台), the Middle Dignitary, 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."...


Mu Ursae Majoris is a M-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...

 red giant
Red giant
A red giant is a luminous giant star of low or intermediate mass in a late phase of stellar evolution. The outer atmosphere is inflated and tenuous, making the radius immense and the surface temperature low, somewhere from 5,000 K and lower...

 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 3.0m. It is approximately 250 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 the 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...

. It is classified as a Semiregular 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 2.99m to 3.33m.

Spectroscopically it has been determined that this is a double star
Multiple star
A multiple star consists of three or more stars which appear from the Earth to be close to one another in the sky. This may result from the stars being physically close and gravitationally bound to each other, in which case it is physical, or this closeness may be merely apparent, in which case...

 with a companion a mere 1.5 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....

from the primary with a rotation period of 230 days.
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