23 Ursae Majoris
Encyclopedia
23 Ursae Majoris, or 23 UMa, is a triple star 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....

 Ursa Major
Ursa Major
Ursa Major , also known as the Great Bear, is a constellation visible throughout the year in most of the northern hemisphere. It can best be seen in April...

. Its main components, 23 UMa A and 23 UMa B, are approximately 75.5 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...

.

The primary component, 23 Ursae Majoris A, is a yellow-white F-type
Stellar classification
In astronomy, stellar classification is a classification of stars based on their spectral characteristics. The spectral class of a star is a designated class of a star describing the ionization of its chromosphere, what atomic excitations are most prominent in the light, giving an objective measure...

 subgiant 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 +3.65. At a separation of 22.7 arcseconds is the 9th magnitude 23 Ursae Majoris B. A and B form a physical binary
Binary star
A binary star is a star system consisting of two stars orbiting around their common center of mass. The brighter star is called the primary and the other is its companion star, comes, or secondary...

. The third, optical, component, 23 Ursae Majoris C, is a magnitude +10.5 star 99.6 arcseconds away.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK