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X Trianguli Australis, HD134453, HIP74582

X Trianguli Australis is a pulsating star that can be located in the constellation of TriangulumAustrale. X Trianguli Australis is the brightest star in Triangulum Australe 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.

HIP74582 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD134453.

X Trianguli Australis has alternative name(s), X TrA.

Location of X Trianguli Australis

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 X Trianguli Australis, the location is 15h 14m 19.17 and -70d04`46.0 .

Proper Motion of X Trianguli Australis

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 -7.51 ± 0.36 miliarcseconds/year towards the north and 4.30 ± 0.44 miliarcseconds/year east if we saw them in the horizon.

Physical Properties (Temperature, Radius) of X Trianguli Australis

X Trianguli Australis has a spectral type of N0v. This means the star is a star. The star is 7163.00000000 Parsecs from the Galactic Centre or terms of Light Years is 23363.0803307200000000s. The star has a B-V Colour Index of 3.27 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 0 Kelvin. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.

X Trianguli Australis Apparent and Absolute Magnitudes

X Trianguli Australis has an apparent magnitude of 5.75 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 -2.56 If you used the 2007 Parallax value, you would get an absolute magnitude of -2.03. 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 X Trianguli Australis

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 2.18 which gave the calculated distance to X Trianguli Australis as 1496.16 light years away from Earth or 458.72 parsecs. It would take a spaceship travelling at the speed of light, 1496.16 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 2.78 which put X Trianguli Australis at a distance of 1173.25 light years or 359.71 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 7,163.00 Parsecs or 23,363.08 Light Years. The Galacto-Centric Distance is the distance from the star to the Centre of the Galaxy which is Sagittarius A*.

Variable Type of X Trianguli Australis

The star is a pulsating Slow Irregular variable type which means that its size changes over time. The Variable Type is usually named after the first star of that type to be spotted. X Trianguli Australis brightness ranges from a magnitude of 5.702 to a magnitude of 5.413 over its variable period. The smaller the magnitude, the brighter the star. Its variable/pulsating period lasts for 0.3 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.

X Trianguli Australis Facts

Alternative Names

Traditional/Proper NameX Trianguli Australis
Short NameX TrA
Hipparcos Library I.D.74582
Henry Draper Designation134453

Visual Facts

Star Type star
Absolute Magnitude-2.56 / -2.03
Visual / Apparent Magnitude5.75
Naked Eye VisibleYes - Magnitudes
Right Ascension (R.A.)15h 14m 19.17
Declination (Dec.)-70d04`46.0
Galactic Latitude-10.52 degrees
Galactic Longitude314.60 degrees
1997 Distance from Earth2.18 Parallax (milliarcseconds)
 1496.16 Light Years
 458.72 Parsecs
2007 Revised Distance from Earth2.78 Parallax (milliarcseconds)
 1173.25 Light Years
 359.71 Parsecs
Galacto-Centric Distance23,363.08 Light Years / 7,163.00 Parsecs
Proper Motion Dec.-7.51 ± 0.36 milliarcseconds/year
Proper Motion RA.4.30 ± 0.44 milliarcseconds/year
B-V Index3.27
Radial Velocity-3.20 ± 1.50 km/s
Spectral TypeN0v

Variable Star Details

Variable Star ClassPulsating
Variable Star TypeSlow Irregular
Mean Variability Period in Days0.283
Variable Magnitude Range (Brighter - Dimmer)5.413 - 5.702

Estimated Facts

Sources and Links

SIMBAD SourceLink

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