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Pherkad Minor

Pherkard, 11 Ursae Minoris

Proper NamesPherkad Minor, Pherkard
Bayer DesignationNone
Flamsteed Number11 Ursae Minoris
HR (BSC)5714
ConstellationUrsa Minor
Right Ascension15h 17m 6s
Declination+71° 49' 26"
Distance412 light years
126 parsecs
MagnitudeApparent: +5.0
Absolute: -0.4
Spectral ClassK4III orange giant
Planets in this systemPherkad Minor b (11 Ursae Minoris b), gas giant
Optimum VisibilityMay / June (Usually visible from northern latitudes)
NotesA relatively hot and young star some fiften times the diameter of the Sun, Pherkad is a white giant star that shows slight but rapid variability, oscillating in brightness over a period of hours. It is classified as a Delta Scuti variable, though it is unusual for that class and may have unique properties of its own.

Pherkad is one of the two stars that form the Guardians of the Pole in Ursa Minor, and near it in the sky lies a far less prominent star named Pherkad Minor, a name that translates as the 'lesser calf' (the more prominent Pherkad is sometimes called Pherkad Major to distinguish it from this fainter neighbour). This star is also occasionally known as Pherkard, a name that is, rather confusingly, also sometimes used of the quite separate star Delta Ursae Minoris.

The brighter white star to the east of Pherkad Minor is Pherkad itself, designated Gamma Ursae Minoris. Despite the related names, the two stars are unconnected, and Pherkad falls some seventy-five light years farther from the Sun than its less luminous neighbour in the sky. Imagery provided by Aladin sky atlas

Pherkad Major and Pherkad Minor are not related to one another, except for their apparent proximity in the skies of Earth. At a distance of some 412 light years from the Sun, Pherkad Minor is about seventy-five light years closer than Pherkad Major. Pherkad Minor appears far less bright in the sky because it is intrinsically less luminous than its more distant giant neighbour. Though it is outshone by Pherkad Major, orange Pherkad Minor is nonetheless a giant star in its own right, and us considerably more luminous than the Sun.

Pherkad Minor is known to have a gas giant in orbit around it, designated 11 Ursae Minoris b (named from the star's Flamsteed number). This is an immensely massive body, more than ten times the mass of Jupiter, pursuing an orbit that carries it around its parent star every 516 days.


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