26 Draconis
Encyclopedia
26 Draconis is a triple star
system in the constellation
Draco
, located 46 light years from the Sun
. Two of the system components, A and B, form a spectroscopic binary that completes an orbit every 76 years. The composite spectral classification of the AB pair is G0V, which decomposes to individual spectral types F9V and K3V. A 1962 study estimated the masses of these two stars as 1.30 and 0.83 times the mass of the Sun
, respectively. The stars are considered moderately metal-poor compared to the Sun, which means they have a lower proportion of elements other than hydrogen or helium.
The third component, GJ 685, is a red dwarf
spectral classification of M1V. As of 1970, this star is separated by 12.2 arc seconds with the AB pair and they share a common proper motion. The space velocity components of 26 Draconis are U = +36.5, V = −4.3 and W = −21.8 km/s. This system is on an orbit through the Milky Way
galaxy that has an eccentricity of 0.14, taking it as close as 23.1 kly and as far as 30.4 kly from the galactic core. The inclination of this orbit carries the star system as much as 0.75 kly above the plane of the galactic disk. This system may be a member of the Ursa Major moving group
.
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...
system 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....
Draco
Draco (constellation)
Draco is a constellation in the far northern sky. Its name is Latin for dragon. Draco is circumpolar for many observers in the northern hemisphere...
, located 46 light years from the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
. Two of the system components, A and B, form a spectroscopic binary that completes an orbit every 76 years. The composite spectral classification of the AB pair is G0V, which decomposes to individual spectral types F9V and K3V. A 1962 study estimated the masses of these two stars as 1.30 and 0.83 times the mass of the Sun
Solar mass
The solar mass , , is a standard unit of mass in astronomy, used to indicate the masses of other stars and galaxies...
, respectively. The stars are considered moderately metal-poor compared to the Sun, which means they have a lower proportion of elements other than hydrogen or helium.
The third component, GJ 685, is a red dwarf
Red dwarf
According to the Hertzsprung-Russell diagram, a red dwarf star is a small and relatively cool star, of the main sequence, either late K or M spectral type....
spectral classification of M1V. As of 1970, this star is separated by 12.2 arc seconds with the AB pair and they share a common proper motion. The space velocity components of 26 Draconis are U = +36.5, V = −4.3 and W = −21.8 km/s. This system is on an orbit through the Milky Way
Milky Way
The Milky Way is the galaxy that contains the Solar System. This name derives from its appearance as a dim un-resolved "milky" glowing band arching across the night sky...
galaxy that has an eccentricity of 0.14, taking it as close as 23.1 kly and as far as 30.4 kly from the galactic core. The inclination of this orbit carries the star system as much as 0.75 kly above the plane of the galactic disk. This system may be 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...
.