{{short description|Triple-star system in the constellation Coma Berenices}} {{Starbox begin}} {{Starbox image | image = {{Location mark |image=Coma Berenices constellation map.svg|alt=|float=center|width=280 |label=|position=right |mark=Red circle.svg|mark_width=10|mark_link=37 Comae Berenices |x=235|y=132 }} | caption = Location of 37 Comae Berenices (circled in red) }} {{Starbox observe | epoch = J2000.0 | constell = [[Coma Berenices]]<ref name=Anderson2012/> | pronounce = | ra = {{RA|13|00|16.46725}}<ref name=GaiaDR2/> | dec = {{DEC|+30|47|06.0644}}<ref name=GaiaDR2/> | appmag_v = 4.88<ref name=auriere/> }} {{Starbox character | type = [[subgiant]]<ref name=Tsvetkova2017/> | class = {{nowrap|G9 III CH-2 CN-1}}<ref name=perkins1989/> | b-v = {{Val|1.165|0.014}}<ref name=Anderson2012/> | u-b = | variable = [[RS Canum Venaticorum variable|RS CVn]]<ref name=Samus2017/> }} {{Starbox astrometry | radial_v = −14.34<ref name=Famaey2005/> | prop_mo_ra = −18.662<ref name=GaiaDR2/> | prop_mo_dec = −5.802<ref name=GaiaDR2/> | parallax = 4.6981 | p_error = 0.2586 | parallax_footnote = <ref name=GaiaDR2/> | absmag_v = −1.62<ref name=Anderson2012/> }} {{Starbox detail | source = <ref name=auriere/> | mass = 5.25 | radius = 38.2 | rotational_velocity = {{Val|11|1}}<ref name=Tsvetkova2017/> | rotation = 111&nbsp;days<ref name=Tsvetkova2017/> | luminosity_bolometric = 590 | temperature = 4,625<ref name=Tsvetkova2017/> | metal_fe = −0.05<ref name=Tsvetkova2017/> | gravity = 2.3 | age_gyr = }} {{Starbox catalog | names = {{odlist| F=37 Com | F2=13 CVn | V=LU Com | BD=+31°2434 | HD=112989 | HIP=63462 | HR=4929 | SAO=96265 }}<ref name=SIMBAD/> }} {{Starbox reference | Simbad = 37+Com }} {{Starbox end}}

'''37 Comae Berenices''' is a [[variable star]] system located around 690<ref name=GaiaDR2/>&nbsp;[[light year]]s away from the Sun in the northern [[constellation]] of [[Coma Berenices]].<ref name=SIMBAD/> It has the [[variable star designation]] '''LU Comae Berenices'''. 37 Comae Berenices was a later [[Flamsteed designation]] of '''13 Canum Venaticorum'''.<ref name=Wagman1987/> This object is visible to the [[naked eye]] as a faint, yellow-hued star with a baseline [[apparent visual magnitude]] of 4.88.<ref name=auriere/> It is drifting closer to the Earth with a heliocentric [[radial velocity]] of −14&nbsp;km/s.<ref name=Famaey2005/>

[[File:LUComLightCurve.png|thumb|left|A [[light curve]] for LU Comae Berenices, adapted from Henry ''et al.'' (2000).<ref name="Henry"/> The plotted brightness is the average of the [[Strömgren photometric system|Strömgren]] b and y magnitudes.]] Tokovinin (2008) catalogued this as a wide triple star system.<ref name=Tsvetkova2017/> The primary component is an aging [[giant star]], currently in the [[Hertzsprung gap]],<ref name=Tsvetkova2017/> with a [[stellar classification]] of {{nowrap|G9 III CH-2 CN-1}}.<ref name=perkins1989/> It is a [[weak G-band star]],<ref name=Tsvetkova2017/> a luminous [[giant star]] with a [[carbon]] abundance about a factor of 5 lower than is typical for such stars.<ref name=LamRies1981/> José Renan De Medeiros ''et al.'' announced that the star is a variable star, in 1999.<ref name="deMedeiros1999"/> It was given its variable star designation in 2003.<ref name="Kazarovets2003"/> This is a variable star most likely of the [[RS Canum Venaticorum variable|RS CVn type]] with an amplitude of 0.15 in magnitude,<ref name=Samus2017/> and it displays [[magnetic activity]].<ref name=Tsvetkova2017/> It has 5.25 times the [[mass of the Sun]] and, having exhausted the supply of hydrogen at its [[stellar core|core]], has expanded to 38 times the [[Sun's radius]].<ref name=auriere/>

{{clear left}} ==References== <references> <ref name=GaiaDR2>{{cite DR2|1464753314462948480}}</ref>

<ref name=SIMBAD>{{cite simbad | title=37 Com | access-date=2019-07-16 }}</ref>

<ref name=Anderson2012>{{cite XHIP|63462}}</ref>

<ref name="deMedeiros1999">{{cite journal | last1=de Medeiros | first1=J. R. | last2=Konstantinova-Antova | first2=R. K. | last3=da Silva | first3=J. R. P. | title=The peculiar single giant HD 112989: rotation, activity and evolution | journal=Astronomy and Astrophysics | date=July 1999 | volume=347 | pages=550–555 | bibcode=1999A&A...347..550D }}</ref>

<ref name="Kazarovets2003">{{cite journal | last1=Kazarovets | first1=E. V. | last2=Kireeva | first2=N. N. | last3=Samus |first3=N. N. | last4=Durlevich | first4=O. V. |title=The 77th Name-List of Variable Stars | journal=Information Bulletin on Variable Stars | date=May 2003 | volume=5422 | pages=1–56 | bibcode=2003IBVS.5422....1K }}</ref>

<ref name="Henry">{{cite journal | last1=Henry |first1=Gregory W. | last2=Fekel |first2=Francis C. | last3=Henry |first3=Stephen M. | last4=Hall |first4=Douglas S. | title=Photometric Variability in a Sample of 187 G and K Giants | journal=The Astrophysical Journal Supplement Series | date=September 2000 |volume=130 |issue=1 |pages=201–225 |doi=10.1086/317346 |bibcode=2000ApJS..130..201H |s2cid=17160805 |doi-access=free}}</ref>

<ref name=Tsvetkova2017>{{cite journal | title=Magnetic field structure in single late-type giants: The weak G-band giant 37 Comae from 2008 to 2011 | last1=Tsvetkova | first1=S. | last2=Petit | first2=P. | last3=Konstantinova-Antova | first3=R. | last4=Aurière | first4=M. | last5=Wade | first5=G. A. | last6=Palacios | first6=A. | last7=Charbonnel | first7=C. | last8=Drake | first8=N. A. | display-authors=1 | journal=Astronomy & Astrophysics | volume=599 | id=A72 | pages=13 | date=March 2017 | arxiv=1612.02669 | bibcode=2017A&A...599A..72T | doi=10.1051/0004-6361/201527034 | s2cid=118944156 }}</ref>

<ref name=perkins1989>{{cite journal | last1=Keenan | first1=Philip C. | last2=McNeil | first2=Raymond C. | title=The Perkins catalog of revised MK types for the cooler stars | journal=Astrophysical Journal Supplement Series | volume=71 | pages=245 | year=1989 | bibcode=1989ApJS...71..245K | doi=10.1086/191373 }}</ref>

<ref name=auriere>{{cite journal | title=The magnetic fields at the surface of active single G-K giants | display-authors=1 | journal=Astronomy & Astrophysics | last1=Aurière | first1=M. | last2=Konstantinova-Antova | first2=R. | last3=Charbonnel | first3=C. | last4=Wade | first4=G. A. | last5=Tsvetkova | first5=S. | last6=Petit | first6=P. | last7=Dintrans | first7=B. | last8=Drake | first8=N. A. | last9=Decressin | first9=T. | last10=Lagarde | first10=N. | last11=Donati | first11=J.-F. | last12=Roudier | first12=T. | last13=Lignières | first13=F. | last14=Schröder | first14=K.-P. | last15=Landstreet | first15=J. D. | last16=Lèbre | first16=A. | last17=Weiss | first17=W. W. | last18=Zahn | first18=J.-P. | volume=574 | pages=A90 | year=2015 | bibcode=2015A&A...574A..90A | arxiv=1411.6230 | doi=10.1051/0004-6361/201424579 | s2cid=118504829 }}</ref>

<ref name=Famaey2005>{{Cite journal | title= Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters | journal= Astronomy and Astrophysics | display-authors=1 | last1=Famaey | first1=B. | last2=Jorissen | first2=A. | last3=Luri | first3=X. | last4=Mayor | first4=M. | last5=Udry | first5=S. | last6=Dejonghe | first6=H. | last7=Turon | first7=C. | volume=430 | pages=165–186 | year=2005 | bibcode=2005A&A...430..165F | arxiv=astro-ph/0409579 | doi=10.1051/0004-6361:20041272 | s2cid= 17804304 }}</ref>

<ref name=LamRies1981>{{cite journal | last1=Lambert | first1=D. L. |last2=Ries | first2=L. M. | title=Carbon, nitrogen, and oxygen abundances in G and K giants | journal=[[Astrophysical Journal]] | volume=248 | pages=228–248 | date=Aug 15, 1981 | bibcode=1981ApJ...248..228L | doi=10.1086/159147 | doi-access=free }}</ref>

<ref name=Wagman1987>{{cite journal | last=Wagman | first=M. | title=Flamsteed's Missing Stars | journal=Journal for the History of Astronomy | volume=18 | page=214 |date=August 1987 | issue=3 | bibcode=1987JHA....18..209W | doi=10.1177/002182868701800305 | s2cid=118445625 }}</ref>

<ref name=Samus2017>{{cite journal | last1=Samus | first1=N. N. | last2=Kazarovets | first2=E. V. | last3=Durlevich | first3=O. V. | last4=Kireeva | first4=N. N. | last5=Pastukhova | first5=E. N. | display-authors=1 | title=General Catalogue of Variable Stars | version=GCVS 5.1 | journal=Astronomy Reports | year=2017 | volume=61 | issue=1 | pages=80–88 | doi=10.1134/S1063772917010085 | bibcode=2017ARep...61...80S | s2cid=125853869 }}</ref> </references>

{{Stars of Coma Berenices}}

<!-- Properties --> [[Category:G-type giants]] [[Category:RS Canum Venaticorum variables]] [[Category:Triple star systems]] <!-- Catalogues --> [[Category:Coma Berenices]] [[Category:Durchmusterung objects|BD+31 2434]] [[Category:Flamsteed objects|Comae Berenices, 37]] [[Category:Henry Draper Catalogue objects|112989]] [[Category:Hipparcos objects|063462]] [[Category:Bright Star Catalogue objects|4924]] [[Category:Objects with variable star designations|Comae Berenices, LU]]