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Omicron Ophiuchi B - HD156350 - HIP84625

Omicron Ophiuchi B is a white to yellow luminous giant star that can be located in the constellation of Ophiuchus. Omicron Ophiuchi B is the Bayer Classification for the star. HIP84625 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD156350. The Id of the star in the Gould Star Catalogue is 113. Stars in the southern hemisphere are more likely to have a Gould Id than the northern hemisphere. For example, there are no Gould classified stars in Ursa Major. Omicron Ophiuchi B has alternative name(s), 39 Ophiuchi , 39 Oph. Omicron Ophiuchi B is a multiple star system with 2 stars orbiting in its solar system.

Location of Omicron Ophiuchi B

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 Omicron Ophiuchi B, the location is 17h 18m 00.64 and -24d17`02.7 .

Proper Motion of Omicron Ophiuchi B

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 -008.10 ± 000.63 towards the north and -057.47 ± 001.09 east if we saw them in the horizon.

Physical Properties (Colour, Temperature, Radius) of Omicron Ophiuchi B

Omicron Ophiuchi B has a spectral type of G8/K0II. This means the star is a white to yellow luminous giant star. The star has a B-V Colour Index of 0.51 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 6,089 Kelvin.

Omicron Ophiuchi B has been calculated as 5.94 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 4,133,219.97.km.

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

Omicron Ophiuchi B Apparent and Absolute Magnitudes

Omicron Ophiuchi B has an apparent magnitude of 6.59 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 0.75 If you used the 2007 Parallax value, you would get an absolute magnitude of 1.63. 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 Omicron Ophiuchi B

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 6.78 which gave the calculated distance to Omicron Ophiuchi B as 481.07 light years away from Earth or 147.49 parsecs. It would take a spaceship travelling at the speed of light, 481.07 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 10.18 which put Omicron Ophiuchi B at a distance of 320.40 light years or 98.23 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.

Omicron Ophiuchi B Facts

Alternative Names

Short Name39 Oph
Bayer DesignationOmicron Ophiuchi B
Alternative Name(s)39 Ophiuchi
Hipparcos Library I.D.84625
Gould I.D.113
Henry Draper Designation156350

Visual Facts

Star Typeluminous giant star
Absolute Magnitude0.75 / 1.63
Apparent Magnitude6.59
Right Ascension (R.A.)17h 18m 00.64
Declination (Dec.)-24d17`02.7
1997 Distance from Earth6.78 Parallax (milliarcseconds)
 481.07 Light Years
 147.49 Parsecs
2007 Revised Distance from Earth10.18 Parallax (milliarcseconds)
 320.40 Light Years
 98.23 Parsecs
Proper Motion Dec.-8.10 ± 0.63 milliarcseconds/year
Proper Motion RA.-57.47 ± 1.09 milliarcseconds/year
B-V Index0.51
Spectral TypeG8/K0II
Colour(G) White to Yellow

Companions (Multi-Star and Exoplanets) Facts

Stars in Solar System2
Companion StarsOmicron Ophiuchi

Estimated Facts

Radius (x the Sun)5.94
Calculated Effective Temperature6,089 Kelvin

Sources and Links

SIMBAD SourceLink

Related Stars


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