Universe GuideSearchTwitterComments

UU Ursae Minoris

UU Ursae Minoris Facts

UU Ursae Minoris's Alternative Names

HIP76832 is the reference name for the star in the Hipparcos Star Catalogue. The Gliese ID of the star is GL 597AB. The star was part of the original catalogue devised by German Astronomer Wilheim Gliese of stars located within 20 parsecs of Earth. Star Names

UU Ursae Minoris has alternative name(s) :- , UU UMi.

More details on objects' alternative names can be found at Star Names .

Location of UU Ursae Minoris

The location of the variable star in the night sky 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 object is compared to the celestial equator and is expressed in degrees. For UU Ursae Minoris, the location is 15h 41m 14.70 and +75° 59` 40.7 .

Radial Velocity and Proper Motion of UU 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 -758.27 ± 2.21 miliarcseconds/year towards the north and 776.36 ± 2.40 miliarcseconds/year east if we saw them in the horizon.

The Radial Velocity, that is the speed at which the star is moving away/towards the Sun is -10.10 km/s with an error of about 10.00 km/s . When the value is negative then the star and the Sun are getting closer to one another, likewise, a positive number means that two stars are moving away. Its nothing to fear as the stars are so far apart, they won't collide in our life-time, if ever.

Physical Properties (Colour, Temperature) of UU Ursae Minoris

UU Ursae Minoris has a spectral type of M4. This means the star is a red variable star. The star is 7,404.00 Parsecs from the Galactic Centre or in terms of Light Years is 24,149.13 s. The star has a B-V Colour Index of 1.65 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 3,628 Kelvin.

UU Ursae Minoris Radius has been calculated as being 0.11 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 77,257.21.km. If you need the diameter of the star, you just need to multiple the radius by 2. However with the 2007 release of updated Hipparcos files, the radius is now calculated at being round 0.11. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.

UU Ursae Minoris Apparent and Absolute Magnitudes

UU Ursae Minoris has an apparent magnitude of 12.22 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 11.64 If you used the 2007 Parallax value, you would get an absolute magnitude of 11.60. 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 UU Ursae Minoris

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 76.57 which gave the calculated distance to UU Ursae Minoris as 42.60 light years away from Earth or 13.06 parsecs. It would take a spaceship travelling at the speed of light, 42.60 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 75.13 which put UU Ursae Minoris at a distance of 43.41 light years or 13.31 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.

Using the 2007 distance, the star is roughly 2,745,365.44 Astronomical Units from the Earth/Sun give or take a few. An Astronomical Unit is the distance between Earth and the Sun. The number of A.U. is the number of times that the star is from the Earth compared to the Sun.

The star's Galacto-Centric Distance is 7,404.00 Parsecs or 24,149.13 Light Years. The Galacto-Centric Distance is the distance from the star to the Centre of the Galaxy which is Sagittarius A*. UU Ursae Minoris brightness ranges from a magnitude of 12.399 to a magnitude of 12.036 over its variable period. The smaller the magnitude, the brighter the star. Its variable/pulsating period lasts for 0.3 days (variability).

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.

Hide Explanations
Show GridLines

Additional UU Ursae Minoris Facts and Figures

Visual Facts


Primary / Proper / Traditional NameUU Ursae Minoris
Alternative NamesHIP 76832, Gliese 597AB, UU UMi
Spectral TypeM4
Constellation's Main StarNo
Multiple Star SystemNo / Unknown
Star TypeVariable Star
ColourRed
GalaxyMilky Way
ConstellationUrsa Minor
Absolute Magnitude 11.64 / 11.60
Visual / Apparent Magnitude12.22
Naked Eye VisibleRequires a 4.5 - 6 Inch Telescope - Magnitudes
Right Ascension (R.A.)15h 41m 14.70
Declination (Dec.)+75° 59` 40.7
Galactic Latitude36.97 degrees
Galactic Longitude111.13 degrees
1997 Distance from Earth76.57 Parallax (milliarcseconds)
 42.60 Light Years
 13.06 Parsecs
2007 Distance from Earth75.13 Parallax (milliarcseconds)
 43.41 Light Years
 13.31 Parsecs
 2,745,365.44 Astronomical Units
Galacto-Centric Distance24,149.13 Light Years / 7,404.00 Parsecs
Proper Motion Dec.-758.27 ± 2.21 milliarcseconds/year
Proper Motion RA.776.36 ± 2.40 milliarcseconds/year
B-V Index1.65
Radial Velocity-10.10 ± 10.00 km/s
Eccentricity0.58
Semi-Major Axis12480.00

Companions (Multi-Star and Exoplanets) Facts


Exoplanet CountNone/Unaware

Variable Star Details


Mean Variability Period in Days0.276
Variable Magnitude Range (Brighter - Dimmer)12.036 - 12.399

Estimated Calculated Facts


Radius (x the Sun)0.11
Effective Temperature3,628 Kelvin

Sources and Links


SIMBAD SourceLink

Related Stars


Comments and Questions

There's no register feature and no need to give an email address if you don't need to. All messages will be reviewed before being displayed. Comments may be merged or altered slightly such as if an email address is given in the main body of the comment.

   
x
This website is using cookies. More info. That's Fine