Pherkad (Gamma Ursae Minoris) Star Facts

Pherkad, also known as Gamma Ursae Minoris is a giant star located in the constellation of Ursa Minor, The Small Bear. Pherkad is a major star and forms part of the constellation. Pherkad is the traditional/proper name for the star, whilst Gamma Ursae Minoris is the Bayer Designation for the star. A list of additional names and identifications is in the facts list at the bottom of the page.

Based on the spectral type (A3II-III), Pherkad colour is blue - white, although not the hottest stars, they are considerably hotter than our own star which is white.

Pherkad temperature is in the range of between 7,500 and 10,000 Kelvin. Pherkad effective temperature is 6,306 Kelvin which is hotter than the Sun's effective temperature, which is 5,777 Kelvin. Based on a parallax of 6.7, Pherkad distance from Earth can be calculated at being 486.81 light years away or 147.28 parsecs.

Pherkad is a naked-eye star, so you don't need a telescope or binoculars when you look up on a clear night. The lower the magnitude, the easier it will be to see it.

Location

The location of the Pherkad in the night sky is determined by the right ascension (R.A.) and declination (Dec.). These are equivalent to the Longitude and Latitude on Earth. The Right Ascension (Longitude) is expressed in time (hh:mm:ss) and is how far the star is along Earth's celestial equator. If the R.A. is positive, then it's eastwards and vice versa.

The Declination (Latitude) is how far north or south the object is compared to the celestial equator and is expressed in degrees. If the value is positive, it is north of the celestial equator. For Pherkad, the location is 15h 20m 43.75 and +71° 50` 02.3 .

Based on the location of Ursa Minor, Pherkad can be located in the northern hemisphere of the celestial sky. The celestial hemisphere is equivalent to the hemispheres on Earth. Pherkad is north of the Ecliptic. The Ecliptic is the path that the Earth takes as it orbits the Sun. As the Earth is titled, we therefore have Celestial and Ecliptic hemispheres and they can be different for a star.

Physical Properties

Pherkad Luminosity

Luminosity is the amount of energy a star pumps out relative to the amount that our star, the Sun, gives out. Our star, the Sun's value is 1. Pherkad Luminosity figure of 2,850.387 comes from the Vizier online catalogue. The star generates more energy than our star.

Pherkad Size (Radius)

Pherkad radius has been calculated as being 44.73 times bigger than the Sun. The Sun's radius is 695,800km, therefore, the Pherkad radius is an estimated 31,123,134.km. If you need the star's diameter, you just need to multiply the radius by 2.

Magnitude (Apparent / Absolute / Visible)

A number represents a star’s magnitude, whether apparent/visual or absolute. The smaller the number, the brighter the star is. The Sun is the brightest star and therefore has the lowest of all magnitudes, -26.74. A faint star will have a high number.

Pherkad apparent magnitude is 3, which is a measure of the star's brightness as seen from Earth. Apparent Magnitude is also known as Visual Magnitude.

If you use the 1997 parallax value, Pherkad' absolute magnitude is -2.84. If you use the 2007 parallax value, Pherkad' absolute magnitude is -2.87. Absolute Magnitude is the star's apparent magnitude from 10 parsecs or 32.6 light years. The magnitude assumes nothing is between the object and the viewer, such as dust clouds. To compare different stars' actual brightness, you would best use Absolute rather than Apparent Magnitude.

Pherkad is visible from Earth without needing binoculars or a telescope. The lower the Apparent Magnitude of a star or other object is, the easier it is to see in the night sky. An object with a magnitude greater than 6.5 cannot be seen without a telescope or other device.

Pherkad Fact List

The table is scrollable if you can't see everything, just swipe the table to see the hidden information.

Key Facts

Primary Name:

Spectral Type:

Star Type:

Colour:

Galaxy:

Constellation:

Celestial Hemisphere:

Main Star

Visual / Apparent Magnitude

Visible From Earth

Absolute Magnitude

Radial Velocity

Eccentricity:

Semi-Major Axis

Luminosity (Lsun)

Effective Temp. (Kelvin):

Radius

Location/Coordinates

Right Ascension

Declination

Galactic Latitude

Galactic Longitude

Galacto-Centric Distance:

Distance from Earth

Parallax

Light Years

Parsecs

Astronomical Units (A.U.)

Proper Motion

Declination

Right Ascension

Miscellaneous Facts

B-V Index

Variable Star Class

Variable Star Type

Alternate Names