|Beta Comae Berenices|
|Designation|| β Comae Berenices|
|Right ascension||13h 11m 52.3938s|
|Declination||+27° 52′ 41.4536″|
|Type of object||Main sequence star|
|Magnitude|| Apperent Mag: +4.23|
Absolute Mag: +4.42
|Distance from Earth||29.78 ly|
|Radial velocity||5.46±0.09 km/s|
|Proper motion|| RA: -801.44 mas/yr|
Dec.: 882.04 mas/yr
Beta Comae Berenices (β Comae Berenices) is a main sequence star in the constellation of Coma Berenices. Its Bayer designation of Beta is slightly unusual since it is brighter than the Alpha star; the Alpha star should be the brightest star in the constellation. It is also unusual in that it is one of the few stars that can be seen with the unaided eye that are similar in luminosity to the Sun.
Properties and Structure
The star is situated 29.78 light years away and is though to be a little larger than the Sun, with a mass of 1.05 solar masses and a radius 1.13 times larger.  Its surface temperature is marginally hotter than the Sun's at 6,006 K but its larger size means it outputs roughly 51% more energy than Sol. Beta Comae rotates about twice as fast as Sol. Because of the faster rotation and up-and-down convection in its outer gas layers, the star is probably also more magnetically active than the Sun. It has a long-term activity cycle of 16.6 years (roughly six years longer than Sun's), and might have a secondary cycle of 9.6 years. Analysis of the star's spectrum suggests it has a Sun-like magnetic field and possess starspots and flares. The star is believed to have 1.05 to 2.29 more heavy elements like iron than the Sun.
It is thought that Beta Comae Berenices is part of a multi-star system where two or more stars orbit each other closely. There is thought to be only one additional, much dimmer, star with an apparent magnitude of +10.1 compared to Beta Comae Berenices' +4.3. No planets have been observed around Beta Comae Berenices.
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