18 Boötis
Encyclopedia
18 Boötis is a star
in the constellation Boötes
about 85 light years away from Earth. Its apparent magnitude is 5.40 and its absolute magnitude is 3.3.
It is a white subgiant of spectral type F5IV. It has a luminosity
four times and a radius
1.6 times solar.
18 Boötis is believed to be a stream star 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...
in the constellation Boötes
Boötes
Boötes is a constellation in the northern sky, located between 0° and +60° declination, and 13 and 16 hours of right ascension on the celestial sphere. The name comes from the Greek Βοώτης, Boōtēs, meaning herdsman or plowman...
about 85 light years away from Earth. Its apparent magnitude is 5.40 and its absolute magnitude is 3.3.
It is a white subgiant of spectral type F5IV. It has a luminosity
Luminosity
Luminosity is a measurement of brightness.-In photometry and color imaging:In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre.The luminosity function...
four times and a radius
Radius
In classical geometry, a radius of a circle or sphere is any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter. If the object does not have an obvious center, the term may refer to its...
1.6 times solar.
18 Boötis is believed to be a stream star 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...
.