Tau Sagittarii Star Facts (Type, Distance, Magnitude, Age, Colour, Location and more)

Tau Sagittarii is a giant star located in the constellation of Sagittarius, Half-Man/Half-Horse Archer. Tau Sagittarii is a major star and forms part of the constellation.

Based on the spectral type (K1/K2III), Tau Sagittarii colour is orange to red, these are stars that are cooler than our own star.

Tau Sagittarii temperature is in the range of between 3,700 and 5,200 Kelvin. Tau Sagittarii effective temperature is 4,707 Kelvin which is cooler than the Sun's effective temperature which is 5,777 Kelvin. Based on a parallax of 26.82, Tau Sagittarii distance from Earth can be calculated at being 121.61 light years away or 36.91 parsecs.

Tau Sagittarii is a naked-eye star, so you don't need a telescope or binoculars when you look up on a clear night. The lower the magnitude, the easier it will be to see it.

Location

The location of the Tau Sagittarii in the night sky is determined by the right ascension (R.A.) and declination (Dec.). These are equivalent to the Longitude and Latitude on Earth. The Right Ascension (Longitude) is expressed in time (hh:mm:ss) and is how far the star is along Earth's celestial equator. If the R.A. is positive, then it's eastwards and vice versa.

The Declination (Latitude) is how far north or south the object is compared to the celestial equator and is expressed in degrees. If the value is positive, it is north of the celestial equator. For Tau Sagittarii, the location is 19h 06m 56.44 and -27° 40` 11.3 .

Based on the location of Sagittarius, Tau Sagittarii can be located in the southern hemisphere of the celestial sky. The celestial hemisphere is equivalent to the hemispheres on Earth. Tau Sagittarii is on the Ecliptic. The Ecliptic is the path that the Earth takes as it orbits the Sun. As the Earth is titled, we therefore have Celestial and Ecliptic hemispheres and they can be different for a star.

Physical Properties

Spectral Type

Tau Sagittarii spectral type of K1/K2III which means its colour and type is orange to red giant star. There is no relationship between colour and size. For example, a red star can be large or small. Small stars are more energy efficient than larger stars and live longer.

Tau Sagittarii Luminosity

Luminosity is the amount of energy a star pumps out relative to the amount that our star, the Sun, gives out. Our star, the Sun's value is 1. Tau Sagittarii Luminosity figure of 93.67 comes from the Vizier online catalogue. The star generates more energy than our star.

Iron Abundance

Tau Sagittarii Iron Abundance is -0.14 with an error value of 0.04 Fe/H, with the Sun having a value of 1 to put it into context. The value comes from the Hipparcos Extended Catalog.

Magnitude (Apparent / Absolute / Visible)

A number represents a star’s magnitude, whether apparent/visual or absolute. The smaller the number, the brighter the star is. The Sun is the brightest star and therefore has the lowest of all magnitudes, -26.74. A faint star will have a high number.

Tau Sagittarii apparent magnitude is 3.32, which is a measure of the star's brightness as seen from Earth. Apparent Magnitude is also known as Visual Magnitude.

If you use the 1997 parallax value, Tau Sagittarii' absolute magnitude is 0.48. If you use the 2007 parallax value, Tau Sagittarii' absolute magnitude is 0.46. Absolute Magnitude is the star's apparent magnitude from 10 parsecs or 32.6 light years. The magnitude assumes nothing is between the object and the viewer, such as dust clouds. To compare different stars' actual brightness, you would best use Absolute rather than Apparent Magnitude.

Tau Sagittarii is visible from Earth without needing binoculars or a telescope. The lower the Apparent Magnitude of a star or other object is, the easier it is to see in the night sky. An object with a magnitude greater than 6.5 cannot be seen without a telescope or other device.