Gamma Ursae Minoris
Encyclopedia
Gamma Ursae Minoris (γ UMi, γ Ursae Minoris; also 13 UMi) is a slightly 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...

 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....

 Ursa Minor
Ursa Minor
Ursa Minor , also known as the Little Bear, is a constellation in the northern sky. Like the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle, whence the name Little Dipper...

. It also has the common name Pherkad. Together with Beta Ursae Minoris
Beta Ursae Minoris
Beta Ursae Minoris is the second brightest star in the bowl of the "Little Dipper,"the constellation Ursa Minor. It has the traditional name Kochab. Kochab's magnitude is 2.07. It is 16 degrees from Polaris. The star is an orange giant and is 126.4 ± 2.5 light years from Earth. It is 130 times...

, Gamma forms the end of the dipper pan of the "Little Dipper". The name "Pherkad" derives from the Arabic فرقد farqad "calf", short for aḫfa al farkadayn "the dim one of the two calves", Pherkad and Kochab. (The full name Ahfa al Farkadain is now applied to ζ UMi.) γ UMi is sometimes called Pherkad Major to distinguish it from 11 Ursae Minoris
11 Ursae Minoris
11 Ursae Minoris or 11 UMi is a 5th magnitude K-type giant star located approximately 398 light years away in the constellation Ursa Minor. It is sometimes named Pherkard or Pherkad Minor, the later name to distinguish it from Pherkad which is Gamma Ursae Minoris...

 Pherkad Minor.

Together, Pherkad and Kochab are also called the "Guardians of the Pole."

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 Pole
Purple Forbidden enclosure
The Purple Forbidden enclosure is one of the San Yuan or Three enclosures. Stars and constellations of this group lie near the north celestial pole and visible all year from temperate latitudes in the Northern Hemisphere.-Asterisms:The asterisms are :...

, refers to an asterism consisting of γ Ursae Minoris, β Ursae Minoris
Beta Ursae Minoris
Beta Ursae Minoris is the second brightest star in the bowl of the "Little Dipper,"the constellation Ursa Minor. It has the traditional name Kochab. Kochab's magnitude is 2.07. It is 16 degrees from Polaris. The star is an orange giant and is 126.4 ± 2.5 light years from Earth. It is 130 times...

, 5 Ursae Minoris, 4 Ursae Minoris and Σ 1694. Consequently, γ Ursae Minoris itself is known as , representing , meaning Crown Prince

Gamma Ursae Minoris has 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...

 +3.00. It is approximately 480 light years 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...

 and is of 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...

 A3, meaning it has a surface temperature of 7,500 to 11,000 kelvin
Kelvin
The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all...

s. It is classified as 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 by 0.05 magnitudes with a period of 3.43 hours. It is 1100 times more luminous than the Sun, and possesses a radius 15 times that of the Sun.
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