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Pi Indi - HD208149 - HIP108281

Pi Indi is a blue star that can be located in the constellation of Indus. Pi Indi is the Bayer Classification for the star. HIP108281 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD208149.

Location of Pi Indi

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 Pi Indi, the location is 21h 56m 14.04 and -57d53`58.6 .

Proper Motion of Pi Indi

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 006.63 ± 000.23 towards the north and 017.33 ± 000.40 east if we saw them in the horizon.

Physical Properties (Colour, Temperature, Radius) of Pi Indi

Pi Indi has a spectral type of A3m.... This means the star is a blue star. The star has a B-V Colour Index of 0.21 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 7,325 Kelvin.

Pi Indi has been calculated as 5.64 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 3,924,388.40.km.

Pi Indi Apparent and Absolute Magnitudes

Pi Indi has an apparent magnitude of 6.17 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 0.06 If you used the 2007 Parallax value, you would get an absolute magnitude of 0.40. 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 Pi Indi

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 6.00 which gave the calculated distance to Pi Indi as 543.61 light years away from Earth or 166.67 parsecs. It would take a spaceship travelling at the speed of light, 543.61 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 7.00 which put Pi Indi at a distance of 465.95 light years or 142.86 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.

Pi Indi Facts

Alternative Names

Bayer DesignationPi Indi
Hipparcos Library I.D.108281
Henry Draper Designation208149

Visual Facts

Star Type star
Absolute Magnitude0.06 / 0.40
Apparent Magnitude6.17
Right Ascension (R.A.)21h 56m 14.04
Declination (Dec.)-57d53`58.6
1997 Distance from Earth6.00 Parallax (milliarcseconds)
 543.61 Light Years
 166.67 Parsecs
2007 Revised Distance from Earth7.00 Parallax (milliarcseconds)
 465.95 Light Years
 142.86 Parsecs
Proper Motion Dec.6.63 ± 0.23 milliarcseconds/year
Proper Motion RA.17.33 ± 0.40 milliarcseconds/year
B-V Index0.21
Spectral TypeA3m...
Colour(A) blue

Estimated Facts

Radius (x the Sun)5.64
Calculated Effective Temperature7,325 Kelvin

Sources and Links

SIMBAD SourceLink

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