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Omega Geminorum, 42 Geminorum, HD52497, HIP33927, HR2630

Omega Geminorum is a white to yellow luminous giant star that can be located in the constellation of Gemini. Omega Geminorum is the brightest star in Gemini based on the Hipparcos 2007 apparent magnitude. The star can be seen with the naked eye, that is, you don't need a telescope/binoculars to see it.

Omega Geminorum is the Bayer Classification for the star. The Id of the star in the Yale Bright Star Catalogue is HR2630. HIP33927 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD52497.

Location of Omega Geminorum

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 Omega Geminorum, the location is 07h 02m 24.78 and +24d 12` 55.6 .

Proper Motion of Omega Geminorum

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 -0.25 ± 0.15 miliarcseconds/year towards the north and -6.74 ± 0.26 miliarcseconds/year east if we saw them in the horizon.

Physical Properties (Colour, Temperature, Radius) of Omega Geminorum

Omega Geminorum has a spectral type of G5II. This means the star is a white to yellow luminous giant star. The star is 7829.00000000 Parsecs from the Galactic Centre or terms of Light Years is 25535.3282017600000000s. The star has a B-V Colour Index of 0.95 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 5,082 Kelvin.

Omega Geminorum Radius has been calculated as being 55.83 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 38,846,437.87.km. However with the 2007 release of updated Hipparcos files, the radius is now calculated at being round 50.22. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.

Omega Geminorum Apparent and Absolute Magnitudes

Omega Geminorum has an apparent magnitude of 5.20 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 -3.33 If you used the 2007 Parallax value, you would get an absolute magnitude of -3.10. 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 Omega Geminorum

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 1.97 which gave the calculated distance to Omega Geminorum as 1655.65 light years away from Earth or 507.61 parsecs. It would take a spaceship travelling at the speed of light, 1655.65 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 2.19 which put Omega Geminorum at a distance of 1489.33 light years or 456.62 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.

The star's Galacto-Centric Distance is 7,829.00 Parsecs or 25,535.33 Light Years. The Galacto-Centric Distance is the distance from the star to the Centre of the Galaxy which is Sagittarius A*.

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.

Omega Geminorum Facts

Alternative Names

Flamsteed Name42 Geminorum
Flamsteed Short Name42 Gem
Bayer DesignationOmega Geminorum
Hipparcos Library I.D.33927
Yale Bright Star Catalogue (HR) Id2630
Bonner DurchmusterungBD+24 1502
Henry Draper Designation52497

Visual Facts

Star Typeluminous giant star
Absolute Magnitude-3.33 / -3.10
Visual / Apparent Magnitude5.20
Naked Eye VisibleYes - Magnitudes
Right Ascension (R.A.)07h 02m 24.78
Declination (Dec.)+24d 12` 55.6
Galactic Latitude13.05 degrees
Galactic Longitude192.18 degrees
1997 Distance from Earth1.97 Parallax (milliarcseconds)
 1655.65 Light Years
 507.61 Parsecs
2007 Revised Distance from Earth2.19 Parallax (milliarcseconds)
 1489.33 Light Years
 456.62 Parsecs
Galacto-Centric Distance25,535.33 Light Years / 7,829.00 Parsecs
Proper Motion Dec.-0.25 ± 0.15 milliarcseconds/year
Proper Motion RA.-6.74 ± 0.26 milliarcseconds/year
B-V Index0.95
Radial Velocity-9.10 ± 0.40 km/s
Spectral TypeG5II
Colour(G) White to Yellow

Estimated Facts

Calculated Effective Temperature5,082 Kelvin

Sources and Links

SIMBAD SourceLink

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