HD 111395

{{Short description|Star in the constellation Coma Berenices}} {{Starbox begin}} {{Starbox image | image = [[Image:LWComLightCurve.png|250px]] | caption = A [[Photometric_system#Photometric_letters|visual band]] [[light curve]] for LW Comae Berenices, adapted from Strassmeier ''et al.'' (1997)<ref name=Strassmeier1997/> }} {{Starbox observe | epoch = J2000 | constell = [[Coma Berenices]]<ref name=Anderson2012/> | ra = {{RA|12|48|47.048}}<ref name=GaiaDR3/> | dec = {{DEC|+24|50|24.82}}<ref name=GaiaDR3/> | appmag_v = 6.29<ref name=Anderson2012/> }} {{Starbox character | type = [[main sequence]]<ref name=GaiaDR3/> | class = G7V<ref name=Gray2006/> | b-v = {{Val|0.703|0.002}}<ref name=Anderson2012/> | u-b = | variable = [[BY Draconis variable|BY Dra]]<ref name=Samus2017/> }} {{Starbox astrometry | radial_v = {{Val|−8.936|0.0064}}<ref name=Soubiran2013/> | prop_mo_ra = {{val|−334.908}} | prop_mo_dec = {{val|−105.517}} | pm_footnote = <ref name=GaiaDR3/> | parallax = 58.4858 | p_error = 0.0293 | parallax_footnote = <ref name=GaiaDR3/> | absmag_v = 5.15<ref name=Anderson2012/> }} {{Starbox detail | mass = {{Val|1.08|0.04}}<ref name=McCarthy2014/> | radius = {{Val|0.93|0.01}}<ref name=GaiaDR2/> | gravity = {{Val|4.543|0.05}}<ref name=McCarthy2014/> | metal_fe = {{Val|0.08|0.02}}<ref name=McCarthy2014/> | temperature = {{Val|5649|38|17|fmt=commas}}<ref name=GaiaDR2/> | luminosity = {{Val|0.799|0.001}}<ref name=GaiaDR2/> | rotational_velocity = {{Val|3.8|0.8}}<ref name=McCarthy2014/> | age_gyr = 1.0<ref name=gaspar2016/> or 1.01−1.73<ref name=Vican2012/> }} {{Starbox catalog | names = {{odlist | V=LW Com | BD=+25°2568 | FK5=3021 | GJ=486.1 | HD=111395 | HIP=62523 | HR=4864 | SAO=82511 }}<ref name=SIMBAD/> }} {{Starbox reference | Simbad = HD+111395 }} {{Starbox end}}

'''HD 111395''' is a single,<ref name=Fuhrmann2017/> [[variable star]] in the northern [[constellation]] of [[Coma Berenices]]. It has the [[variable star designation]] '''LW Comae Berenices''';<ref name=Samus2017/> ''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.<ref name=Anderson2012/> Based upon [[stellar parallax|parallax]] measurements, it is located at a distance of 55.8 [[light year]]s from the [[Sun]].<ref name=GaiaDR3/> The star is drifting closer with a [[radial velocity]] of −8.9 km/s.<ref name=Soubiran2013/> It is a member of the [[Eta Chamaeleontis]] stellar kinematic group.<ref name=Nakajima2012/>

This object is a [[G-type main-sequence star]] with a [[stellar classification]] of G7V.<ref name=Gray2006/> Klaus G. Strassmeier ''et al.'' announced their discovery that HD 111395 is a variable star, in 1997.<ref name="Strassmeier1997"/> It was given its variable star designation in 2006.<ref name="Kazarovets2006"/> It is a [[BY Draconis variable]] that varies in brightness by about 0.10 magnitude over a period of 15.8 days,<ref name=Samus2017/> which is interpreted as the [[rotation period]] of the star. (Messina et al. (2003) suspect the actual rotation period may be half that: 7.9 days.<ref name=Messina2003/>) It has an [[magnetic activity|active]] [[chromosphere]]<ref name=Strassmeier1997/> and is a source for [[X-ray astronomy|X-ray emission]].<ref name=Greiner2015/>

The star is around a billion years old with a [[projected rotational velocity]] of 3.8 km/s.<ref name=McCarthy2014/> It has slightly above solar [[metallicity]] − the term astronomers use for the relative abundance of elements other than hydrogen and helium. The mass of the star is 8% greater than the Sun,<ref name=McCarthy2014/> but it has 93% of the [[Sun's radius]].<ref name=GaiaDR2/> It is radiating 80% of the luminosity of the Sun from its [[photosphere]] at an [[effective temperature]] of 5649 K.<ref name=GaiaDR2/> An [[infrared excess]] indicates a cold [[debris disk]] is orbiting the star at a distance of {{Val|17.48|ul=AU}} with a mean temperature of 60 K. The disk has an estimated mass of {{Val|5.86|e=−6|ul=Earth mass}}.<ref name=gaspar2016/>

==References== {{Reflist|refs=

<ref name=SIMBAD>{{cite simbad | title=HD 111395 | access-date=2019-11-28 }}</ref>

<ref name=Soubiran2013>{{citation | title=The catalogue of radial velocity standard stars for Gaia. I. Pre-launch release | display-authors=1 | last1=Soubiran | first1=C. | last2=Jasniewicz | first2=G. | last3=Chemin | first3=L. | last4=Crifo | first4=F. | last5=Udry | first5=S. | last6=Hestroffer | first6=D. | last7=Katz | first7=D. | journal=Astronomy & Astrophysics | volume=552 | id=A64 | pages=11 | date=April 2013 | bibcode=2013A&A...552A..64S | arxiv=1302.1905 | doi=10.1051/0004-6361/201220927 | s2cid=56094559 }}</ref>

<ref name=Gray2006>{{citation | title=Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 parsecs: The Northern Sample I | display-authors=1 | last1=Gray | first1=R. O. | first2=C. J. | last2=Corbally | first3=R. F. | last3=Garrison | first4=M. T. | last4=McFadden | first5=P. E. | last5=Robinson | journal=The Astronomical Journal | volume=132 | issue=1 | pages=161–170 |date=July 2006 | bibcode=2006AJ....132..161G | arxiv=astro-ph/0603770 | doi=10.1086/504637 | s2cid=119476992 | postscript=. }}</ref>

<ref name="Kazarovets2006">{{citation | postscript=. | title=The 78th Name-List of Variable Stars | display-authors=1 | last1=Kazarovets | first1=E. V. | last2=Samus | first2=N. N. | last3=Durlevich | first3=O. V. | last4=Kireeva | first4=N. N. | last5=Pastukhova | first5=E. N. | journal=Information Bulletin on Variable Stars | date=August 2006 | volume=5721 | pages=1-45 | bibcode=2006IBVS.5721....1K | url=https://ibvs.konkoly.hu/pub/ibvs/5701/5721.pdf | access-date=8 February 2025}}</ref>

<ref name=Samus2017>{{citation | title=General Catalogue of Variable Stars | postscript=. | display-authors=1 | 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. | version=5.1 | journal=Astronomy Reports | year=2017 | volume=61 | issue=1 | pages=80–88 | bibcode=2017ARep...61...80S | doi=10.1134/S1063772917010085 | s2cid=125853869 }}</ref>

<ref name=McCarthy2014>{{citation | title=Characterizing the AB Doradus Moving Group via High-resolution Spectroscopy and Kinematic Traceback | last1=McCarthy | first1=Kyle | last2=Wilhelm | first2=Ronald J. | journal=The Astronomical Journal | volume=148 | issue=4 | id=70 | pages=13 | date=October 2014 | doi=10.1088/0004-6256/148/4/70 | arxiv=1407.1076 | bibcode=2014AJ....148...70M | s2cid=119296096 | postscript=. }}</ref>

<ref name=Fuhrmann2017>{{citation | title=Multiplicity among Solar-type Stars | last1=Fuhrmann | first1=K. | last2=Chini | first2=R. | last3=Kaderhandt | first3=L. | last4=Chen | first4=Z. | display-authors=1 | journal=The Astrophysical Journal | volume=836 | issue=1 | pages=139 | year=2017 | bibcode=2017ApJ...836..139F | postscript=. | doi=10.3847/1538-4357/836/1/139 | doi-access=free }}</ref>

<ref name=Greiner2015>{{citation | title=Optical counterparts of ROSAT X-ray sources in two selected fields at low vs. high Galactic latitudes | last1=Greiner | first1=J. | last2=Richter | first2=G. A. | journal=Astronomy & Astrophysics | arxiv=1408.5529 | volume=575 | id=A42 | pages=67 | date=March 2015 | postscript=. | doi=10.1051/0004-6361/201322844 | bibcode=2015A&A...575A..42G | s2cid=59501196 }}</ref>

<ref name=gaspar2016>{{citation | display-authors=1 | last1=Gáspár | first1=András | last2=Rieke | first2=George H. | last3=Ballering | first3=Nicholas | title=The Correlation between Metallicity and Debris Disk Mass | journal=The Astrophysical Journal | postscript=. | volume=826 | issue=2 | pages=171 | year=2016 | bibcode=2016ApJ...826..171G | arxiv=1604.07403 | doi=10.3847/0004-637X/826/2/171 | s2cid=119241004 | doi-access=free }}</ref>

<ref name=Nakajima2012>{{citation | last1=Nakajima | first1=Tadashi | last2=Morino | first2=Jun-Ichi | title=Potential Members of Stellar Kinematic Groups within 30 pc of the Sun | journal=The Astronomical Journal | postscript=. | volume=143 | issue=1 | page=2 | date=January 2012 | doi=10.1088/0004-6256/143/1/2 | doi-access=free | bibcode=2012AJ....143....2N }}</ref>

<ref name=Vican2012>{{citation | last1=Vican | first1=Laura | title=Age Determination for 346 Nearby Stars in the Herschel DEBRIS Survey | journal=The Astronomical Journal | volume=143 | issue=6 | page=135 |date=June 2012 | doi=10.1088/0004-6256/143/6/135 | bibcode=2012AJ....143..135V | arxiv=1203.1966 | s2cid=118539505 | postscript=. }}</ref>

<ref name=Strassmeier1997>{{citation | title=Photospheric and chromospheric activity of the bright and single G5 dwarf HR 4864 = HD 111395 | display-authors=1 | last1=Strassmeier | first1=K. G. | last2=Granzer | first2=Th. | last3=Weber | first3=M. | journal=Information Bulletin on Variable Stars | volume=4538 | page=1 | date=December 1997 | bibcode=1997IBVS.4538....1S | postscript=. }}</ref>

<ref name=Messina2003>{{citation | title=Dependence of coronal X-ray emission on spot-induced brightness variations in cool main sequence stars | last1=Messina | first1=S. | last2=Pizzolato | first2=N. | last3=Guinan | first3=E. F. | last4=Rodonò | first4=M. | display-authors=1 | journal=Astronomy and Astrophysics | volume=410 | pages=671–684 | date=November 2003 | issue=2 | postscript=. | doi=10.1051/0004-6361:20031203 | bibcode=2003A&A...410..671M | doi-access=free }}</ref>

}}

{{Stars of Coma Berenices}}

[[Category:G-type main-sequence stars]] [[Category:BY Draconis variables]] [[Category:Circumstellar disks]]  [[Category:Coma Berenices]] [[Category:Bright Star Catalogue objects|4864]] [[Category:Durchmusterung objects]] [[Category:Gliese and GJ objects|0486]] [[Category:Henry Draper Catalogue objects|111395]] [[Category:Hipparcos objects|62523]] [[Category:Objects with variable star designations|Comae Berenices, LW]]