Mu Herculis

{{Short description|Quadruple star system in the constellation Hercules}}

{{Starbox begin

| name=Mu Herculis }}

{{Starbox image

| image = 250px

| caption =Historical view of the Hercules constellation showing Mu Herculis (μ Her) as one of stars in the hero's elbow.}}

{{Starbox observe 2s

| epoch=J2000

| component1=μ Her Aab (μ¹ Her)

| constell=Hercules

| ra1={{RA|17|46|27.52667}}

| dec1={{DEC|+27|43|14.4379}}

| appmag_v1={{nowrap|3.417 ± 0.014}}

| component2=μ Her BC (μ² Her)

| ra2={{RA|17|46|25.079}}{{cite journal|title=2MASS All-Sky Catalog of Point Sources|date=2003|journal=VizieR On-line Data Catalog|author=Cutri, R. M.|volume = 2246|display-authors=etal|bibcode=2003yCat.2246....0C}}

| dec2={{DEC|+27|43|01.45}}

| appmag_v2=10.2 / 10.7{{cite web|url=http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/wds/orb6|title=Sixth Catalog of Orbits of Visual Binary Stars|work=United States Naval Observatory|access-date=23 March 2017|archive-date=1 August 2017|archive-url=https://web.archive.org/web/20170801102553/http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/wds/orb6}}

}}

{{Starbox character

| component=μ Her Aab

| class=G5IV / M4V

| b-v=+0.76{{cite journal|author1=Mermilliod, J.-C.|title=Compilation of Eggen's UBV data, transformed to UBV (unpublished)|journal=Catalogue of Eggen's UBV Data|page=0|url=http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?1986EgUBV........0M&db_key=AST&nosetcookie=1|date=1986|bibcode= 1986EgUBV........0M}}

| u-b=+0.40

| variable=

}}

{{Starbox character|no_heading=y

| component=μ Her BC

| class=M3.5V{{cite journal |doi=10.1051/0004-6361/201525803 |title=CARMENES input catalogue of M dwarfs |journal=Astronomy & Astrophysics |volume=577 |pages=A128 |year=2015 |last1=Alonso-Floriano |first1=F. J. |last2=Morales |first2=J. C. |last3=Caballero |first3=J. A. |last4=Montes |first4=D. |last5=Klutsch |first5=A. |last6=Mundt |first6=R. |last7=Cortés-Contreras |first7=M. |last8=Ribas |first8=I. |last9=Reiners |first9=Ansgar |last10=Amado |first10=P. J. |last11=Quirrenbach |first11=A. |last12=Jeffers |first12=S. V. |arxiv=1502.07580 |bibcode=2015A&A...577A.128A |s2cid=53135130 |url=http://goedoc.uni-goettingen.de/goescholar/bitstream/handle/1/12402/aa25803-15.pdf }}{{Dead link|date=September 2023 |bot=InternetArchiveBot |fix-attempted=yes }}

| b-v=+1.50

| u-b=+1.00

}}

{{Starbox astrometry

| component1=μ Her Aab

| radial_v=−17.07 ± 0.12

| prop_mo_ra=−291.66

| prop_mo_dec=−749.60

| parallax=120.33

| p_error=0.16

| parallax_footnote=

| absmag_v=3.82 ± 0.02

| component2=μ Her BC

| prop_mo_ra2=−343.35{{cite journal|bibcode=2008A&A...488..401R|doi=10.1051/0004-6361:200809775|arxiv=0806.1009|title=PPM-Extended (PPMX) – a catalogue of positions and proper motions|journal=Astronomy and Astrophysics|volume=488|issue=1|page=401|year=2008|last1=Röser|first1=S.|last2=Schilbach|first2=E.|last3=Schwan|first3=H.|last4=Kharchenko|first4=N. V.|last5=Piskunov|first5=A. E.|last6=Scholz|first6=R.-D.|s2cid=17350617}}

| prop_mo_dec2=−743.88

| parallax2 = 119.8871

| p_error2 = 0.2055

| parallax_footnote2 = {{cite Gaia EDR3|4594497834189213184}}

| absmag_v2=+10.26{{cite journal|bibcode=2015AJ....149..106D|title=A 3D Search for Companions to 12 Nearby M Dwarfs|journal=The Astronomical Journal|volume=149|issue=3|page=106|last1=Davison|first1=Cassy L.|last2=White|first2=R. J.|last3=Henry|first3=T. J.|last4=Riedel|first4=A. R.|last5=Jao|first5=W. -C.|last6=Bailey|first6=J. I.|last7=Quinn|first7=S. N.|last8=Cantrell|first8=J. R.|last9=Subasavage|first9=J. P.|last10=Winters|first10=J. G.|year=2015|doi=10.1088/0004-6256/149/3/106|arxiv=1501.05012|s2cid=9719725}}

}}

{{Starbox relpos

| reference =

| primary = μ Her Aab

| component = μ Her BC

| angdistsec = 35

}}

{{Starbox orbit

| reference={{cite journal|bibcode=2016AJ....151..169R|doi=10.3847/0004-6256/151/6/169|arxiv=1604.06494|title=Characterization of the Companion to μ Her|journal=The Astronomical Journal|volume=151|issue=6|page=169|year=2016|last1=Roberts Jr.|first1=Lewis C.|last2=Mason|first2=Brian D.|last3=Aguilar|first3=Jonathan|last4=Carson|first4=Joseph|last5=Crepp|first5=Justin|last6=Beichman|first6=Charles|last7=Brenner|first7=Douglas|last8=Burruss|first8=Rick|last9=Cady|first9=Eric|last10=Luszcz-Cook|first10=Statia|last11=Dekany|first11=Richard|last12=Hillenbrand|first12=Lynne|last13=Hinkley|first13=Sasha|last14=King|first14=David|last15=Lockhart|first15=Thomas G.|last16=Nilsson|first16=Ricky|last17=Oppenheimer|first17=Rebecca|last18=Parry|first18=Ian R.|last19=Pueyo|first19=Laurent|last20=Rice|first20=Emily L.|last21=Sivaramakrishnan|first21=Anand|last22=Soummer|first22=Rémi|last23=Vasisht|first23=Gautam|last24=Veicht|first24=Aaron|last25=Wang|first25=Ji|last26=Zhai|first26=Chengxing|last27=Zimmerman|first27=Neil T.|s2cid=43403927 |doi-access=free }}

| primary=μ Her Aa

| name=μ Her Ab

| period=98.9 ± 22.7

| axis=2.9 ± 0.3

| inclination=62.82 ± 4.66

| node=80.4 ± 1.7

| periastron=B 1921.1 ± 23.8

| eccentricity=0.44 ± 0.06

| periarg=214 ± 16

| k1=1.12 ± 0.10

}}

{{Starbox orbit

| reference=

| primary=μ Her B

| name=μ Her C

| period=43.127 ± 0.013

| axis=1.385 ± 0.038

| inclination=66.06 ± 0.15

| node=60.07 ± 0.17

| periastron=B 2008.335 ± 0.073

| eccentricity=0.1796 ± 0.0009

| periarg=172.85 ± 0.64

}}

{{Starbox detail

| component1 = μ Her Aa

| temperature= {{val|5596|22|fmt=commas}}

| gravity = {{val|4.020|0.025}}

| metal_fe= +{{val|0.26|0.04}}

| rotational_velocity=1.7 ± 0.4

| radius = {{val|1.704|0.016}}

| luminosity= {{val|2.557|0.026}}

| rotation={{val|52|+3|-1}} d

| age_gyr={{val|7.8|+0.3|-0.4}}{{cite journal|bibcode=2017ApJ...836..142G|doi=10.3847/1538-4357/836/1/142|arxiv=1701.03365|title=First Results from the Hertzsprung SONG Telescope: Asteroseismology of the G5 Subgiant Star μ Herculis|journal=The Astrophysical Journal|volume=836|issue=1|page=142|year=2017|last1=Grundahl|first1=F.|last2=Andersen|first2=M. Fredslund|last3=Christensen-Dalsgaard|first3=J.|last4=Antoci|first4=V.|last5=Kjeldsen|first5=H.|last6=Handberg|first6=R.|last7=Houdek|first7=G.|last8=Bedding|first8=T. R.|last9=Pallé|first9=P. L.|last10=Jessen-Hansen|first10=J.|last11=Aguirre|first11=V. Silva|last12=White|first12=T. R.|last13=Frandsen|first13=S.|last14=Albrecht|first14=S.|last15=Andersen|first15=M. I.|last16=Arentoft|first16=T.|last17=Brogaard|first17=K.|last18=Chaplin|first18=W. J.|last19=Harpsøe|first19=K.|last20=Jørgensen|first20=U. G.|last21=Karovicova|first21=I.|last22=Karoff|first22=C.|last23=Rasmussen|first23=P. Kjærgaard|last24=Lund|first24=M. N.|last25=Lundkvist|first25=M. Sloth|last26=Skottfelt|first26=J.|last27=Norup Sørensen|first27=A.|last28=Tronsgaard|first28=R.|last29=Weiss|first29=E.|s2cid=119480210 |doi-access=free }}

| mass=1.11 ± 0.01

| component2 = μ Her Ab

| mass2=0.32

}}

{{Starbox detail|no_heading=y

| component1 = μ Her B

| mass=0.44{{cite web|url=http://www.ctio.noao.edu/~atokovin/stars/stars.php?cat=HR&number=6623|title=Multiple Star Catalog|access-date=2018-12-02|archive-date=2018-12-03|archive-url=https://web.archive.org/web/20181203010914/http://www.ctio.noao.edu/~atokovin/stars/stars.php?cat=HR&number=6623}}

| temperature = 4,050{{cite journal|bibcode=2014MNRAS.443.2561G|title=Trumpeting M dwarfs with CONCH-SHELL: A catalogue of nearby cool host-stars for habitable exoplanets and life|journal=Monthly Notices of the Royal Astronomical Society|volume=443|issue=3|page=2561|last1=Gaidos|first1=E.|last2=Mann|first2=A. W.|last3=Lépine|first3=S.|last4=Buccino|first4=A.|last5=James|first5=D.|last6=Ansdell|first6=M.|last7=Petrucci|first7=R.|last8=Mauas|first8=P.|last9=Hilton|first9=E. J.|year=2014|doi=10.1093/mnras/stu1313|arxiv=1406.7353|doi-access=free}}

| radius = 0.60

| luminosity = 0.087

| metal_fe = +0.21

| component2 = μ Her C

| mass2=0.39

| radius2 = {{val|0.273|0.032}}

| temperature2 = {{val|3100|32|fmt=commas}}

| metal2 = {{M/H|0.39}}

}}

{{Starbox catalog

| names=86 Herculis, Gl 695, HR 6623, BD+27° 2888, HD 161797, LHS 3326/3325, LTT 15266, SAO 85397, FK5 667, LFT 1374, GC 24138, ADS 10786, HIP 86974.

}}

{{Starbox reference

|Simbad=mu+Her | sn=μ Her Aab

|Simbad2=mu.02+Her | sn2=μ Her BC

}}

Mu Herculis (μ Herculis) is a nearby quadruple star system about 27.1 light years from Earth in the constellation Hercules. Its main star, Mu Herculis A is fairly similar to the Sun although more highly evolved with a stellar classification of G5 IV. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified. Its mass is about 1.1 times that of the Sun, and it is beginning to expand to become a giant.

Etymology

In the catalogue of stars in the Calendarium of Al Achsasi Al Mouakket, this star was designated Marfak Al Jathih Al Aisr, which was translated into Latin as Cubitum Sinistrum Ingeniculi, meaning the left elbow of kneeling man.

In Chinese, {{lang|zh|天市左垣}} ({{lang|zh-Latn|Tiān Shì Zuǒ Yuán}}), the Left Wall of Heavenly Market Enclosure, refers to an asterism which represents eleven old states in China, marking the left borderline of the enclosure, consisting of μ Herculis, δ Herculis, λ Herculis, ο Herculis, 112 Herculis, ζ Aquilae, θ¹ Serpentis, η Serpentis, ν Ophiuchi, ξ Serpentis and η Ophiuchi.{{in lang|zh}} 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, {{ISBN|978-986-7332-25-7}}. Consequently, the Chinese name for μ Herculis itself is {{lang|zh|天市左垣三}} ({{lang|zh-Latn|Tiān Shì Zuǒ Yuán sān}}, {{langx|en|the Third Star of Left Wall of Heavenly Market Enclosure}}), represent Jiuhe (九河, lit. meaning nine rivers), possibly for Jiujiang, the prefecture-level city in Jiangxi, China, which is the same literally meaning with Jiuhe.{{in lang|zh}} [http://aeea.nmns.edu.tw/2006/0606/ap060623.html AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 6 月 23 日] {{Webarchive|url=https://web.archive.org/web/20210515003305/http://aeea.nmns.edu.tw/2006/0606/ap060623.html |date=2021-05-15 }}{{in lang|zh}} [http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/e_research_chinengstarzone_b.htm#HeavenlyMarketEnclosure English-Chinese Glossary of Chinese Star Regions, Asterisms and Star Name] {{webarchive|url=https://web.archive.org/web/20100810114313/http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/e_research_chinengstarzone_b.htm |date=2010-08-10 }}, Hong Kong Space Museum. Accessed on line November 23, 2010. From this Chinese title, the name Kew Ho appeared.[https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Hercules*.html Star Name - R.H. Allen p. 238]

Star system

Mu Herculis is a quadruple star system. The brightest star is a well-studied G-type subgiant, whose parameters are precisely determined from asteroseismology. It was believed to be a close binary with a low-mass stellar or a large substellar companion. This was confirmed when low-mass companion was resolved using near-infrared spectroscopy. The companion star is a red dwarf with a spectral type of M4V and a mass of {{solar mass|0.32}}. This pair is also known as Mu¹ Herculis.

The secondary component, also known as Mu² Herculis,{{cite simbad|title=* mu.02 Her|access-date=24 May 2017}} consists of a pair of stars that orbit about each other with a period of about 43 years. Mu Herculis A and the binary pair B-C are separated by some 35 arcseconds.{{cite simbad|title=* mu. Her|access-date=24 May 2017}} The stars B and C, which orbit each other, are separated from each other by 1.385 arcseconds, and have a slightly eccentric orbit, at 0.1796.

References

{{reflist|30em|refs=

{{citation | last1=van Leeuwen | first1=F. | title=Validation of the new Hipparcos reduction | journal=Astronomy and Astrophysics | volume=474 | issue=2 |date=November 2007 | pages=653–664 | doi=10.1051/0004-6361:20078357 | bibcode=2007A&A...474..653V | arxiv=0708.1752 | s2cid=18759600 }}

{{Cite journal |last=Karovicova |first=I. |last2=White |first2=T. R. |last3=Nordlander |first3=T. |last4=Casagrande |first4=L. |last5=Ireland |first5=M. |last6=Huber |first6=D. |date=February 2022 |title=Fundamental stellar parameters of benchmark stars from CHARA interferometry -- III. Giant and subgiant stars |arxiv=2109.13258 |journal=Astronomy & Astrophysics |volume=658 |pages=A48 |doi=10.1051/0004-6361/202142100 |issn=0004-6361}}

{{citation | display-authors=1 | title=Search for Faint Companions to Nearby Solar-like Stars using the Adaptive Optics System at Mount Wilson Observatory | last1=Turner | first1=Nils H. | last2=ten Brummelaar | first2=Theo A. | last3=McAlister | first3=Harold A. | last4=Mason | first4=Brian D. | last5=Hartkopf | first5=William I. | last6=Roberts | first6=Lewis C. Jr. | journal=The Astronomical Journal | volume= 121 | issue=6 | pages=3254–3258 |date=June 2001 | doi=10.1086/321075 | bibcode=2001AJ....121.3254T | doi-access=free }}

{{citation | last=Knobel | first=E. B. | title=Al Achsasi Al Mouakket, on a catalogue of stars in the Calendarium of Mohammad Al Achsasi Al Mouakket | journal=Monthly Notices of the Royal Astronomical Society | volume=55 | issue=8 | page=429 |date=June 1895 | bibcode=1895MNRAS..55..429K | doi=10.1093/mnras/55.8.429| doi-access=free }}

{{citation | title=Models of μ Her with asteroseismic constraints | last1=Yang | first1=Wuming | last2=Meng | first2=Xiangcun | journal=New Astronomy | volume=15 | issue= 4 | pages=367–372 |date=April 2010 | doi=10.1016/j.newast.2009.11.001 | bibcode=2010NewA...15..367Y |arxiv = 0911.0749 | s2cid=119121800 }}

{{citation | last1=Garrison | first1=R. F. | title=Anchor Points for the MK System of Spectral Classification | journal=Bulletin of the American Astronomical Society | volume=25 | page=1319 | date=December 1993 | bibcode=1993AAS...183.1710G | url=http://www.astro.utoronto.ca/~garrison/mkstds.html | access-date=2012-02-04 | archive-date=2019-06-25 | archive-url=https://web.archive.org/web/20190625094716/http://www.astro.utoronto.ca/~garrison/mkstds.html }}

{{cite journal |doi=10.3847/1538-3881/ab23fe |postscript=. |title=The Mass–Activity Relationships in M and K Dwarfs. I. Stellar Parameters of Our Sample of M and K Dwarfs |journal=The Astronomical Journal |volume=158 |issue=2 |pages=56 |year=2019 |last1=Houdebine |first1=Éric R. |last2=Mullan |first2=D. J. |last3=Doyle |first3=J. G. |last4=de la Vieuville |first4=Geoffroy |last5=Butler |first5=C. J. |last6=Paletou |first6=F. |arxiv=1905.07921 |bibcode=2019AJ....158...56H |s2cid=159041104 |doi-access=free }}

}}

External links

Jim Kaler's Stars, University of Illinois: [http://stars.astro.illinois.edu/sow/muher.html MU HER (Mu Herculis)]
SolStation: [http://www.solstation.com/stars/mu-herc4.htm Mu Herculis 4]

Category:Hercules (constellation)

Category:G-type subgiants

Category:M-type main-sequence stars

Category:Durchmusterung objects

161797

Mu Herculis

Etymology

Star system

See also

References

External links