31 Comae Berenices

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31 Comae Berenices
Observation data
Epoch J2000       Equinox J2000
Constellation Coma Berenices
Right ascension 12h 51m 41.91900s [1]
Declination +27° 32 26.5683 [1]
Apparent magnitude  (V)4.87 - 4.97 [2]
Characteristics
Evolutionary stage Hertzsprung gap [3]
Spectral type G0III [4]
Variable type FK Com [2]
Astrometry
Proper motion (μ)RA: −10.990 [1]   mas/yr
Dec.: −8.313 [1]   mas/yr
Parallax (π)11.4933 ± 0.1828  mas [1]
Distance 284 ± 5  ly
(87 ± 1  pc)
Details [4]
Radius 8.9  R
Luminosity 74  L
Surface gravity (log g)3.51  cgs
Temperature 5,660  K
Metallicity [Fe/H]−0.15  dex
Rotation 6.8 d
Rotational velocity (v sin i)67 km/s
Other designations
31 Com, LS Comae Berenices, BD+28°2156, FK5  1332, HD  111812, HIP  62763, HR  4883, SAO  82537 [5]
Database references
SIMBAD data

31 Comae Berenices (31 Com) is a yellow giant star in the constellation Coma Berenices. Its apparent magnitude is about 4.9 and slightly variable. It is a rare FK Comae Berenices variable, a variable star that spins rapidly and has large starspots on its surface. [5] It is currently in the Hertzsprung gap and its outer envelope has just begun convection. [3] In 1989 it was given as a spectral standard for the class G0IIIp. [6]

31 Com is the north galactic pole star, and occasionally goes by the informal name Polaris Galacticum Borealis, coined by Jim Kaler. [7]

In Chinese astronomy, 31 Comae Berenices is called 郎將, Pinyin: Lángjiāng, meaning Captain of the Bodyguards, because this star is marking itself and stand alone in Captain of the Bodyguards asterism, Supreme Palace enclosure mansion (see : Chinese constellation). [8]

Related Research Articles

<span class="mw-page-title-main">Coma Berenices</span> Constellation in the northern hemisphere

Coma Berenices is an ancient asterism in the northern sky, which has been defined as one of the 88 modern constellations. It is in the direction of the fourth galactic quadrant, between Leo and Boötes, and it is visible in both hemispheres. Its name means "Berenice's Hair" in Latin and refers to Queen Berenice II of Egypt, who sacrificed her long hair as a votive offering. It was introduced to Western astronomy during the third century BC by Conon of Samos and was further corroborated as a constellation by Gerardus Mercator and Tycho Brahe. It is the only modern constellation named for a historic person.

7 Boötis is a single star in the northern constellation of Boötes, located 590 light-years away from the Sun. It is barely visible to the naked eye as a dim, yellow-hued star with an apparent visual magnitude of 5.71. 7 Boötis is moving closer to the Earth with a heliocentric radial velocity of −11 km/s.

<span class="mw-page-title-main">FK Comae Berenices</span> Star in the constellation of Coma Berenices

FK Comae Berenices is a variable star that varies in apparent magnitude between 8.14 and 8.33 over a period of 2.4 days. It is the prototype for the FK Comae Berenices class of variable stars. The variability of FK Com stars may be caused by large, cool spots on the rotating surfaces of the stars. This star is thought to be the result of a recent binary merger, resulting in a high rate of both spin and magnetic activity.

<span class="mw-page-title-main">OU Andromedae</span> Rotationally variable star in the constellation Andromeda

OU Andromedae is a rotationally variable star in the constellation Andromeda. Varying between magnitudes 5.87 and 5.94, it has been classified as an FK Comae Berenices variable, but the classification is still uncertain. It has a spectral classification of G1IIIe, meaning that it is a giant star that shows emission lines in its spectrum. It is also likely in its horizontal branch phase of evolution.

Gamma Comae Berenices, Latinized from γ Comae Berenices, is a single, orange-hued star in the northern constellation of Coma Berenices. It is faintly visible to the naked eye, having an apparent visual magnitude of 4.36. Based upon an annual parallax shift of 19.50 mas as seen from Earth, its distance can be estimated as around 167 light years from the Sun. The star is moving away from the Sun with a radial velocity of +3 km/s.

<span class="mw-page-title-main">11 Comae Berenices</span> Binary star system in the constellation Coma Berenices

11 Comae Berenices is a binary star system in the northern constellation of Coma Berenices, located in the sky, east and slightly north of Denebola in Leo, but not nearly as far east as ε Virginis in Virgo. It is about a degree from the elliptical galaxy M85 and two degrees north of the spiral galaxy M100. Based upon an annual parallax shift of 10.7104 mas, the star is located 305 light years away from the Sun. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.72. This body is moving away from the Sun with a heliocentric radial velocity of +44 km/s.

36 Comae Berenices is a single star in the northern constellation of Coma Berenices. It is faintly visible to the naked eye with an apparent visual magnitude of 4.76. The distance to this star, as determined from an annual parallax shift of 9.3 mas, is 349 light years. It is moving closer to the Earth with a heliocentric radial velocity of −1.5 km/s.

<span class="mw-page-title-main">12 Comae Berenices</span> Star in the constellation Coma Berenices

12 Comae Berenices is a binary star system in the northern constellation of Coma Berenices. It is the brightest member of the Coma Cluster and is visible to the naked eye with an apparent visual magnitude of 4.80. Although listed as a suspected variable star, there is no photometric evidence of it being variable in luminosity. However, the radial velocity was found to be variable, as announced by W. W. Campbell in 1910. The first orbital solution was published by Vinter Hansen in the 1940s. It is a double-lined spectroscopic binary with an orbital period of 396.5 days and an eccentricity of 0.566.

41 Comae Berenices is a single, orange-hued star in the northern constellation of Coma Berenices. It is visible to the naked eye, having an apparent visual magnitude of 4.80. Based upon an annual parallax shift of 9.8 mas, it is located around 331 light years away. It is moving closer to the Earth with a heliocentric radial velocity of −17 km/s.

<span class="mw-page-title-main">37 Comae Berenices</span> Triple-star system in the constellation Coma Berenices

37 Comae Berenices is a variable star system located around 690 light years away from the Sun in the northern constellation of Coma Berenices. It has the variable star designation LU Comae Berenices. 37 Comae Berenices was a later Flamsteed designation of 13 Canum Venaticorum. This object is visible to the naked eye as a faint, yellow-hued star with a baseline apparent visual magnitude of 4.88. It is drifting closer to the Earth with a heliocentric radial velocity of −14 km/s.

<span class="mw-page-title-main">14 Comae Berenices</span> Star in the constellation Coma Berenices

14 Comae Berenices is a single star in the northern constellation of Coma Berenices, and is the second brightest member of the Coma Star Cluster. It is a faint star but visible to the naked eye with an apparent visual magnitude of 4.95. Parallax measurements place the star at a distance of about 266 light years.

7 Comae Berenices is a single star located 249 light years away in the northern constellation of Coma Berenices. It is a dim star but visible to the naked eye near the Coma Star Cluster with an apparent visual magnitude of 4.93. The star is moving closer to the Earth with a heliocentric radial velocity of −28 km/s, and is predicted to come as close as 83 light-years in 2.4 million years.

16 Comae Berenices is a single star in the northern constellation of Coma Berenices. 16 Comae Berenices is the Flamsteed designation. It is a member of the Coma Star Cluster and is visible to the naked eye with an apparent visual magnitude of 4.96. Based upon an annual parallax shift of 11.7 mas, it is located about 279 light years away.

<span class="mw-page-title-main">Delta Coronae Borealis</span> Yellow giant star in the constellation Corona Borealis

Delta Coronae Borealis, Latinized from δ Coronae Borealis, is a variable star in the constellation Corona Borealis. Its apparent magnitude varies regularly between apparent magnitude 4.57 and 4.69, and it is around 170 light-years distant.

<span class="mw-page-title-main">28 Monocerotis</span> Star in the constellation Monoceros

28 Monocerotis is a single star in the equatorial constellation of Monoceros. It has an orange-hue and is faintly visible to the naked eye with an apparent visual magnitude of 4.69. The distance to this star is approximately 450 light years based on parallax, and it has an absolute magnitude of −1.00. The star is drifting further away from the Sun with a radial velocity of +26.7 km/s.

71 Cygni is a star in the northern constellation of Cygnus, located 212 light years from the Sun. 71 Cygni is the Flamsteed designation; it has the Bayer designation g Cygni. It is visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 5.22. The star is moving closer to the Earth with a heliocentric radial velocity of −21.5 km/s.

<span class="mw-page-title-main">21 Comae Berenices</span> Star in the constellation Coma Berenices

21 Comae Berenices is a variable star in the northern constellation of Coma Berenices. It has the variable star designation UU Comae Berenices, while 21 Comae Berenices is the Flamsteed designation. According to R. H. Allen, English orientalist Thomas Hyde attributed the ancient title Kissīn to this star, a name that comes from a climbing plant – either bindweed or dog rose. This star has a white hue and is just visible to the naked eye with an apparent visual magnitude that fluctuates around 5.47. Based upon parallax measurements, it is located at a distance of approximately 270 light years away from the Sun. It is a single star but is a confirmed physical member of the Melotte 111 open cluster.

<span class="mw-page-title-main">HD 111395</span> Star in the constellation Coma Berenices

HD 111395 is a single, variable star in the northern constellation of Coma Berenices. It has the variable star designation LW Com, short for LW Comae Berenices; HD 111395 is the Henry Draper Catalogue designation. The star has a yellow hue and is just bright enough to be barely visible to the naked eye with an apparent visual magnitude that fluctuates around 6.29. Based upon parallax measurements, it is located at a distance of 55.8 light years from the Sun. The star is drifting closer with a radial velocity of −8.9 km/s. It is a member of the Eta Chamaeleontis stellar kinematic group.

<span class="mw-page-title-main">V1794 Cygni</span> FK Comae Berenices variable in the constellation Cygnus

V1794 Cygni is a single variable star in the northern constellation Cygnus. It has the identifier HD 199178 from the Henry Draper Catalogue; V1794 Cygni is its variable star designation. With an apparent visual magnitude of 7.24, it's too dim to be visible with the naked eye but can be seen with binoculars. V1794 is located at a distance of 367 light-years (113 pc) based on parallax measurements, but is drifting closer to the Sun with a radial velocity of −31 km/s. It lies superimposed over a region of faint nebulosity to the west of the North American Nebula.

<span class="mw-page-title-main">17 Comae Berenices</span> Multiple star system in the constellation Coma Berenices

17 Comae Berenices is a multiple star system in the northern constellation of Coma Berenices. The brighter component, 17 Com A, is a naked eye star with an apparent visual magnitude of 5.2. It has a faint companion of magnitude 6.6, 17 Com B, positioned at an angular separation of 146.4″ along a position angle of 251°, as of 2018. They are located at a distance of approximately 240 light years from the Sun based on parallax measurements.

References

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  8. Ian Ridpath's Startales - Coma Berenices the Berenice's Hair