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3 Ursae Minoris - HD124063 - HIP68956

3 Ursae Minoris is a blue main sequence dwarf star that can be located in the constellation of UrsaMinor. HIP68956 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD124063. 3 Ursae Minoris has alternative name(s), 3 Ursae Minoris , 3 UMi.

Location of 3 Ursae Minoris

The location of the star in the galaxy is determined by the Right Ascension (R.A.) and Declination (Dec.), these are equivalent to the Longitude and Latitude on the Earth. The Right Ascension is how far expressed in time (hh:mm:ss) the star is along the celestial equator. If the R.A. is positive then its eastwards. The Declination is how far north or south the star is compared to the celestial equator and is expressed in degrees. For 3 Ursae Minoris, the location is 14h 06m 56.48 and +74d35`37.5 .

Proper Motion of 3 Ursae Minoris

All stars like planets orbit round a central spot, in the case of planets, its the central star such as the Sun. In the case of a star, its the galactic centre. The constellations that we see today will be different than they were 50,000 years ago or 50,000 years from now. Proper Motion details the movements of these stars and are measured in milliarcseconds. The star is moving 013.50 ± 000.21 towards the north and -053.42 ± 000.21 east if we saw them in the horizon.

3 Ursae Minoris 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 9.0000000 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, Temperature, Radius) of 3 Ursae Minoris

3 Ursae Minoris has a spectral type of A7V. This means the star is a blue main sequence dwarf star. The star has a B-V Colour Index of 0.16 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 8,017 Kelvin.

3 Ursae Minoris has been calculated as 3.36 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 2,340,756.87.km.

3 Ursae Minoris Apparent and Absolute Magnitudes

3 Ursae Minoris has an apparent magnitude of 6.43 which is how bright we see the star from Earth. Apparent Magnitude is also known as Visual Magnitude. If you used the 1997 Parallax value, you would get an absolute magnitude of 0.79 If you used the 2007 Parallax value, you would get an absolute magnitude of 0.85. 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 3 Ursae Minoris

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 7.45 which gave the calculated distance to 3 Ursae Minoris as 437.80 light years away from Earth or 134.23 parsecs. It would take a spaceship travelling at the speed of light, 437.80 years to get there. We don't have the technology or spaceship that can carry people over that distance yet.

In 2007, Hipparcos data was revised with a new parallax of 7.64 which put 3 Ursae Minoris at a distance of 426.92 light years or 130.89 parsecs. It should not be taken as though the star is moving closer or further away from us. It is purely that the distance was recalculated.

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 Stellar Age, Metallicity or Mass is from the E.U. Exoplanets. The information was obtained as of 12th Feb 2017.

3 Ursae Minoris Facts

Alternative Names

Traditional Name3 Ursae Minoris
Short Name3 UMi
Alternative Name(s)3 Ursae Minoris
Hipparcos Library I.D.68956
Bonner DurchmusterungBD+75 529
Henry Draper Designation124063

Visual Facts

Star Typemain sequence dwarf star
Absolute Magnitude0.79 / 0.85
Apparent Magnitude6.43
Right Ascension (R.A.)14h 06m 56.48
Declination (Dec.)+74d35`37.5
1997 Distance from Earth7.45 Parallax (milliarcseconds)
 437.80 Light Years
 134.23 Parsecs
2007 Revised Distance from Earth7.64 Parallax (milliarcseconds)
 426.92 Light Years
 130.89 Parsecs
Proper Motion Dec.13.50 ± 0.21 milliarcseconds/year
Proper Motion RA.-53.42 ± 0.21 milliarcseconds/year
B-V Index0.16
Spectral TypeA7V
Colour(A) blue

Estimated Facts

Radius (x the Sun)3.36
Luminosity (x the Sun)9.0000000
Calculated Effective Temperature8,017 Kelvin

Sources and Links

SIMBAD SourceLink

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