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Iota Tucanae, HD6793, HIP5268

Iota Tucanae is a white to yellow giant star that can be located in the constellation of Tucana. Iota Tucanae is the brightest star in Tucana 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.

Iota Tucanae is the Bayer Classification for the star. HIP5268 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD6793.

Iota Tucanae has alternative name(s), iot Tuc.

Location of Iota Tucanae

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 Iota Tucanae, the location is 01h 07m 18.57 and -61d46`30.9 .

Proper Motion of Iota Tucanae

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 -11.55 ± 0.19 miliarcseconds/year towards the north and 73.80 ± 0.23 miliarcseconds/year east if we saw them in the horizon.

Iota Tucanae 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 127.0000000 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 Iota Tucanae

Iota Tucanae has a spectral type of G5III. This means the star is a white to yellow giant star. The star is 7374.00000000 Parsecs from the Galactic Centre or terms of Light Years is 24051.2849865600000000s. The star has a B-V Colour Index of 0.8 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 5,286 Kelvin.

Iota Tucanae Radius has been calculated as being 8.07 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 5,612,116.02.km. However with the 2007 release of updated Hipparcos files, the radius is now calculated at being round 8.80. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.

Iota Tucanae Apparent and Absolute Magnitudes

Iota Tucanae has an apparent magnitude of 5.36 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 0.70 If you used the 2007 Parallax value, you would get an absolute magnitude of 0.51. 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 Iota Tucanae

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 11.68 which gave the calculated distance to Iota Tucanae as 279.25 light years away from Earth or 85.62 parsecs. It would take a spaceship travelling at the speed of light, 279.25 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 10.72 which put Iota Tucanae at a distance of 304.26 light years or 93.28 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 7,374.00 Parsecs or 24,051.28 Light Years. The Galacto-Centric Distance is the distance from the star to the Centre of the Galaxy which is Sagittarius A*. Iota Tucanae brightness ranges from a magnitude of 5.534 to a magnitude of 5.472 over its variable period. The smaller the magnitude, the brighter the star. Its variable/pulsating period lasts for 0.1 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.

Iota Tucanae Facts

Alternative Names

Short Nameiot Tuc
Bayer DesignationIota Tucanae
Hipparcos Library I.D.5268
Henry Draper Designation6793

Visual Facts

Star Typegiant star
Absolute Magnitude0.70 / 0.51
Visual / Apparent Magnitude5.36
Naked Eye VisibleYes - Magnitudes
Right Ascension (R.A.)01h 07m 18.57
Declination (Dec.)-61d46`30.9
Galactic Latitude-55.25 degrees
Galactic Longitude299.64 degrees
1997 Distance from Earth11.68 Parallax (milliarcseconds)
 279.25 Light Years
 85.62 Parsecs
2007 Revised Distance from Earth10.72 Parallax (milliarcseconds)
 304.26 Light Years
 93.28 Parsecs
Galacto-Centric Distance24,051.28 Light Years / 7,374.00 Parsecs
Proper Motion Dec.-11.55 ± 0.19 milliarcseconds/year
Proper Motion RA.73.80 ± 0.23 milliarcseconds/year
B-V Index0.80
Radial Velocity-7.80 ± 2.80 km/s
Spectral TypeG5III
Colour(G) White to Yellow

Variable Star Details

Mean Variability Period in Days0.051
Variable Magnitude Range (Brighter - Dimmer)5.472 - 5.534

Estimated Facts

Luminosity (x the Sun)127.0000000
Calculated Effective Temperature5,286 Kelvin

Sources and Links

SIMBAD SourceLink

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