Zeta Tucanae
Encyclopedia
Zeta Tucanae is a star
in the constellation
Tucana
. It is a spectral class F9.5 main sequence
star with an apparent magnitude
of +4.23. Despite having a slightly lower mass, this star is more luminous than the Sun. Based upon parallax
measurements by the Hipparcos
spacecraft, it is approximately 28.0 light years
from Earth
. This is one of the least variable star
s observed during the Hipparcos mission.
The composition and mass of this star are very similar to the Sun, with a slightly lower mass and an estimated age of three billion years. The solar-like qualities make it a target of interest for investigating the possible existence of a life-bearing planet.
Based upon an excess emission of infrared
radiation at 70 micrometres, this system is believed to have a debris disk
. The disk is orbiting the star at a minimum radius of 2.3 astronomical unit
s. It is radiating with a maximum temperature of 218 K. As of 2009, no planet has been discovered in orbit around this star.
Zeta Tucanae is a member of the Ursa Major moving group
of stars. This is a loose association of stars that share a common motion through space. The components of this star's space velocity are U = −60, V = −4 and W = −38 km/s. These correspond to the velocity toward the galactic center, the velocity along
the direction of galactic rotation, and the velocity toward the north galactic pole, respectively. It is orbiting through the galaxy at a mean distance of 8.4 kpc from the galactic center and with an orbital eccentricity
of 0.16.
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
Tucana
Tucana
Tucana is a constellation in the southern sky, created in the late sixteenth century. Its name is Latin for the toucan, a South American bird.-History:...
. It is a spectral class F9.5 main sequence
Main sequence
The main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell...
star with an apparent magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
of +4.23. Despite having a slightly lower mass, this star is more luminous than the Sun. Based upon parallax
Parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. The term is derived from the Greek παράλλαξις , meaning "alteration"...
measurements by the Hipparcos
Hipparcos
Hipparcos was a scientific mission of the European Space Agency , launched in 1989 and operated between 1989 and 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial objects on the sky...
spacecraft, it is approximately 28.0 light years
Light Years
Light Years is the seventh studio album by Australian recording artist Kylie Minogue. It was released on 25 September 2000 by Parlophone and Mushroom Records. The album's style was indicative of her return to "mainstream pop dance tunes"....
from Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
. This is one of the least variable star
Variable star
A star is classified as variable if its apparent magnitude as seen from Earth changes over time, whether the changes are due to variations in the star's actual luminosity, or to variations in the amount of the star's light that is blocked from reaching Earth...
s observed during the Hipparcos mission.
The composition and mass of this star are very similar to the Sun, with a slightly lower mass and an estimated age of three billion years. The solar-like qualities make it a target of interest for investigating the possible existence of a life-bearing planet.
Based upon an excess emission of infrared
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
radiation at 70 micrometres, this system is believed to have a debris disk
Debris disk
A debris disk is a circumstellar disk of dust and debris in orbit around a star. Sometimes these disks contain prominent rings, as seen in the image of Fomalhaut on the right. Debris disks have been found around both evolved and young stars, as well as at least one debris disk in orbit around a...
. The disk is orbiting the star at a minimum radius of 2.3 astronomical unit
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
s. It is radiating with a maximum temperature of 218 K. As of 2009, no planet has been discovered in orbit around this star.
Zeta Tucanae is a member of the Ursa Major moving group
Ursa Major Moving Group
The Ursa Major Moving Group, also known as Collinder 285 or Ursa Major association, is a nearby stellar moving group, a set of stars with common velocities in space and thought to have a common origin. Its core is located roughly 80 light years away...
of stars. This is a loose association of stars that share a common motion through space. The components of this star's space velocity are U = −60, V = −4 and W = −38 km/s. These correspond to the velocity toward the galactic center, the velocity along
the direction of galactic rotation, and the velocity toward the north galactic pole, respectively. It is orbiting through the galaxy at a mean distance of 8.4 kpc from the galactic center and with an orbital eccentricity
Orbital eccentricity
The orbital eccentricity of an astronomical body is the amount by which its orbit deviates from a perfect circle, where 0 is perfectly circular, and 1.0 is a parabola, and no longer a closed orbit...
of 0.16.
External links
- Zeta Tucanae at SolStation.