Beta Canum Venaticorum

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Beta Canum Venaticorum

Observation data Equinox J2000
Constellation	Canes Venatici
Right ascension	12h 33m 44.5446s
Declination	+41° 21′ 26.927″
Apparent magnitude (V)	4.26
Characteristics
Spectral type	G0 V
U-B color index	0.05
B-V color index	0.59
Variable type	Suspected
Astrometry
Radial velocity (Rv)	+6.9 km/s
Proper motion (μ)	RA: -705.06 mas/yr Dec.: 292.93 mas/yr
Parallax (π)	119.19 ± 0.83 mas
Distance	27.4 ± 0.2 ly (8.39 ± 0.06 pc)
Absolute magnitude (MV)	4.65
Details
Mass	1.08 M☉
Radius	1.11 R☉
Luminosity	1.20 L☉
Temperature	5,747 K
Metallicity	97%[1]
Rotation	< 3 km/s
Age	~4 × 109 years
Other designations
Chara, Asterion, Beta CVn, 8 CVn, Gl 475, HR 4785, BD +42°2321, HD 109358, LHS 2579, LTT 13552, GCTP 2895.00, SAO 44230, FK5 470, LFT 924, NSV 5725, HIP 61317.
Database references
SIMBAD	data
ARICNS	data

Beta Canum Venaticorum (β CVn / β Canum Venaticorum) is a yellow G-type main sequence dwarf star in the constellation Canes Venatici. It is the second-brightest star in the constellation.

Along with the brighter star Cor Caroli, the pair form the "southern dog" in this constellation that represents hunting dogs. The name Chara was originally applied to the "southern dog", but it later became used specifically to refer to Beta Canum Venaticorum. Chara means Joy in the Greek language.^[2]

Contents 1 Observations 2 Possibility of Life 3 References 4 External links

[edit] Observations

β CVn is considered to be slightly metal-poor,^[1] which means it has a somewhat lower portion of elements heavier than Helium when compared to the Sun. In terms of mass, age and evolutionary status, however, this star is very similar to the Sun.^[3] As a result it has been called a solar analog.

The spectrum of this star shows a very weak emission of singly-ionized Calcium (Ca II) from the chromosphere, making it a useful reference star for a reference spectrum to compare with other stars in a similar spectral category.^[4] (The Ca II emission lines are readily accessible and can be used to measure the level of activity in a star's chromosphere.)

[edit] Possibility of Life

In 2006, astronomer Margaret Turnbull labelled Beta CVn as the most likely nearby star to host an intelligent species capable of radio astronomy.^[5]

[edit] References

1. ^ ^{a b} M. Cornide, M. Rego (1999). "Iron abundances in G dwarfs". Astrophysics and Space Science 105 (1): 55-65. 
2. ^ Kaler, Jim. Beta Canum Venaticorum. Stars. Retrieved on December 6, 2006.
3. ^ G. F. Porto de Mello, E. F. del Peloso, L. Ghezzi (2006). "Astrobiologically interesting stars within 10 parsecs of the Sun". Astrobiology 6 (2): 308-331. 
4. ^ Herbig, G. H. (1985). "Chromospheric H-alpha emission in F8-G3 dwarfs, and its connection with the T Tauri stars". Astrophysical Journal 289 (1): 269-278. 
5. ^ "Stars searched for extraterrestrials", PhysOrg.com, February 19, 2006. Retrieved on December 6, 2006.

[edit] External links

• Chara. SolStation. Retrieved on December 6, 2006.
• Astronomer announces shortlist of stellar candidates for habitable worlds. SpaceRef.com (February 18, 2006). Retrieved on August 10, 2006.
• β Canum Venaticorum. Alcyone. Retrieved on August 10, 2006.