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Polaris Ab, Alpha Ursae Minoris Ab

Polaris Ab (Alpha Ursae Minoris Ab) is a blue to white main sequence dwarf star that can be located in the constellation of UrsaMinor. Polaris Ab is the brightest star in Ursa Minor based on the Hipparcos 2007 apparent magnitude. The star can not be seen by the naked eye, you need a telescope to see it.

Alpha Ursae Minoris Ab is the Bayer Classification for the star.

Polaris Ab Luminosity

Luminosity is the amount of energy that a star pumps out and its relative to the amount that our star, the Sun gives out. The figure of 2.0000000 that I have given is based on the Spectral Types page that I have found on the Internet. You might find a different figure, one that may have been calculated rather than generalised that I have done. The figure is always the amount times the luminosity of the Sun. It is an imprecise figure because of a number of factors including but not limited to whether the star is a variable star and distance.

Physical Properties (Colour, Radius) of Polaris Ab

Polaris Ab has a spectral type of F6V. This means the star is a blue to white main sequence dwarf star. Polaris Ab lies at a distance of 431.43 light years away from our Sun and our planet Earth or to put it another way, 132.27 parsecs away from the Sun.

Polaris Ab has been calculated as 1.04 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 723,632.00.km.

The star has a companion star which is in orbit close by, it has at least the following companions in close orbit, .

Polaris Ab Apparent and Absolute Magnitudes

Polaris Ab has an apparent magnitude of 9.20 which is how bright we see the star from Earth. Apparent Magnitude is also known as Visual Magnitude. Magnitude, whether it be apparent/visual or absolute magnitude is measured by a number, the smaller the number, the brighter the Star is. Our own Sun is the brightest star and therefore has the lowest of all magnitudes, -26.74. A faint star will have a high number.

Distance to Polaris Ab

Polaris Ab is an estimated 431.43 light years from our Solar System (Earth and Sun). It would take a spaceship 431.43 years travelling at the speed of light to get there. We don't have a space ship that can travel that distance or at that speed yet.

Source of Information

The source of the information if it has a Hip I.D. is from Simbad, the Hipparcos data library based at the University at Strasbourg, France. Hipparcos was a E.S.A. satellite operation launched in 1989 for four years. The items in red are values that I've calculated so they could well be wrong. Information regarding Metallicity and/or Mass is from the E.U. Exoplanets. The information was obtained as of 12th Feb 2017.

Polaris Ab Facts

Alternative Names

Traditional/Proper NamePolaris Ab
Bayer DesignationAlpha Ursae Minoris Ab

Visual Facts

Star Typemain sequence dwarf star
Visual / Apparent Magnitude9.20
Naked Eye VisibleRequires a 7x50 Binoculars - Magnitudes
Distance from the Sun / Earth431.43 Light Years
Spectral TypeF6V
Colour(F) blue to white

Estimated Facts

Radius (x the Sun)1.04
Luminosity (x the Sun)2.0000000

Related Stars

Location of Polaris Ab in Ursa Minor


Polaris Ab (Alpha Ursae Minoris Ab) Location in Ursa Minor

The map was generated using Night Vision, an awesome free application by Brian Simpson.


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