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152 G. Sgr, HD179323, HIP94434

152 G. Sgr is a orange to red giant star that can be located in the constellation of Sagittarius. 152 G. Sgr is the brightest star in Sagittarius 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.

HIP94434 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD179323. The Id of the star in the Gould Star Catalogue is 152. 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.

Location of 152 G. Sgr

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 152 G. Sgr, the location is 19h 13m 13.67 and -25d54`24.3 .

Proper Motion of 152 G. Sgr

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 -9.49 ± 0.19 miliarcseconds/year towards the north and -1.46 ± 0.36 miliarcseconds/year east if we saw them in the horizon.

152 G. Sgr 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 70.0000000 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 152 G. Sgr

152 G. Sgr has a spectral type of K2III. This means the star is a orange to red giant star. The star is 6931.00000000 Parsecs from the Galactic Centre or terms of Light Years is 22606.3813726400000000s. The star has a B-V Colour Index of 1.38 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 4,192 Kelvin.

152 G. Sgr Radius has been calculated as being 79.82 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 55,536,356.68.km. However with the 2007 release of updated Hipparcos files, the radius is now calculated at being round 63.99. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.

152 G. Sgr Apparent and Absolute Magnitudes

152 G. Sgr has an apparent magnitude of 5.79 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 -3.27 If you used the 2007 Parallax value, you would get an absolute magnitude of -2.79. 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 152 G. Sgr

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 1.54 which gave the calculated distance to 152 G. Sgr as 2117.94 light years away from Earth or 649.35 parsecs. It would take a spaceship travelling at the speed of light, 2117.94 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 1.92 which put 152 G. Sgr at a distance of 1698.77 light years or 520.83 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 6,931.00 Parsecs or 22,606.38 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.

152 G. Sgr Facts

Alternative Names

Traditional/Proper Name152 G. Sgr
Hipparcos Library I.D.94434
Gould I.D.152
Henry Draper Designation179323

Visual Facts

Star Typegiant star
Absolute Magnitude-3.27 / -2.79
Visual / Apparent Magnitude5.79
Naked Eye VisibleYes - Magnitudes
Right Ascension (R.A.)19h 13m 13.67
Declination (Dec.)-25d54`24.3
Galactic Latitude-15.98 degrees
Galactic Longitude11.59 degrees
1997 Distance from Earth1.54 Parallax (milliarcseconds)
 2117.94 Light Years
 649.35 Parsecs
2007 Revised Distance from Earth1.92 Parallax (milliarcseconds)
 1698.77 Light Years
 520.83 Parsecs
Galacto-Centric Distance22,606.38 Light Years / 6,931.00 Parsecs
Proper Motion Dec.-9.49 ± 0.19 milliarcseconds/year
Proper Motion RA.-1.46 ± 0.36 milliarcseconds/year
B-V Index1.38
Radial Velocity2.80 ± 0.90 km/s
Spectral TypeK2III
Colour(K) Orange to Red

Estimated Facts

Luminosity (x the Sun)70.0000000
Calculated Effective Temperature4,192 Kelvin

Sources and Links

SIMBAD SourceLink

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