{{short description|Multiple star system in the constellation Scorpius}} {{Starbox begin |name=ν Scorpii }} {{Starbox image | image= {{Location mark |image=Scorpius constellation map.svg |float=center |alt= |label= |position=right |width=260 |mark=Red circle.svg |mark_width=10 |mark_link=ν Scorpii |x=736|y=218 }} |caption=Location of ν Sco (circled) }} {{Starbox observe 2s |constell=Scorpius<ref name=xhip/> |epoch=J2000 |component1=ν Sco A |ra1={{RA|16|11|59.740}}<ref name=TYC2>{{cite journal|title=The Tycho-2 catalogue of the 2.5 million brightest stars|author1=Høg, E.|display-authors=etal|date=2000|journal=Astronomy and Astrophysics|volume=355|pages=L27–L30|bibcode=2000A&A...355L..27H}}</ref> |dec1={{DEC|-19|27|38.33}}<ref name=TYC2/> |appmag_v1=4.349<ref name=TYC2/> |component2=ν Sco B |ra2={{RA|16|11|59.746}}<ref name=TycD>{{cite journal|title=The Tycho double star catalogue|author1=Fabricius, C.|author2=Høg, E.|author3=Makarov, V. V.|author4=Mason, B. D.|author5=Wycoff, G. L.|author6=Urban, S. E.|journal=Astronomy and Astrophysics|volume=384|pages=180–189|date=2002|bibcode=2002A&A...384..180F|doi=10.1051/0004-6361:20011822|doi-access=free}}</ref> |dec2={{DEC|-19|27|36.94}}<ref name=TycD/> |appmag_v2=6.60<ref name=TycD/> }} {{Starbox observe 1s|no_heading=y |component1=ν Sco C |ra={{RA|16|11|58.541}}<ref name=dr3c/> |dec={{DEC|-19|27|00.63}}<ref name=dr3c/> |appmag_v=6.60<ref name=TycD/> }} {{Starbox observe 1s|no_heading=y |component1=ν Sco D |ra={{RA|16|11|58.541}}<ref name=dr3d/> |dec={{DEC|-19|27|00.63}}<ref name=dr3d/> |appmag_v=7.23<ref name=TycD/> }} {{Starbox character |component=ν Sco AB |class=B3V (A)<ref name=msc/> |b-v=+0.05<ref name=UBV>{{cite journal|title=Catalogue of homogeneous data in the UBV photoelectric photometric system|date=1964|journal=Astronomy and Astrophysics Supplement Series|volume=34|pages=1–49|author=Nicolet, B.|bibcode=1978A&AS...34....1N}} Color indices accessed using SIMBAD.</ref> |u-b=−0.63<ref name=UBV/> }} {{Starbox character|no_heading=y |component=ν Sco CD |class=B8V + B9VpSi<ref name=zorec2012>{{cite journal |last1=Zorec |first1=J. |last2=Royer |first2=F. |title=Rotational velocities of A-type stars. IV. Evolution of rotational velocities |journal=Astronomy and Astrophysics |date=2012 |volume=537 |pages=A120 |doi=10.1051/0004-6361/201117691 |arxiv=1201.2052 |bibcode=2012A&A...537A.120Z }}</ref> |b-v=+0.13<ref name=UBV/> |u-b=−0.37<ref name=UBV/> }} {{Starbox astrometry |component1=ν Sco AB |radial_v={{val|+2.4|5}}<ref name=RV>{{cite journal|title=The Revision of the General Catalogue of Radial Velocities|author=Evans, D. S.|journal=Determination of Radial Velocities and Their Applications |date=2006|volume=30 |page=57 |bibcode=1967IAUS...30...57E}}</ref> |prop_mo_ra=−7.65<ref name=HIP/> |prop_mo_dec=−23.71<ref name=HIP/> |parallax=6.88 |p_error=0.76 |parallax_footnote=<ref name=HIP>{{cite journal | title=Validation of the new Hipparcos reduction | last1=van Leeuwen | first1=F. | journal=Astronomy and Astrophysics | volume=474 | issue=2 | pages=653–664 | date=2007 | arxiv=0708.1752 | bibcode=2007A&A...474..653V | doi=10.1051/0004-6361:20078357 |s2cid = 18759600}}</ref> |absmag_v=−1.78<ref name=xhip>{{cite XHIP|79374}}</ref> }} {{Starbox astrometry|no_heading=y |component1=ν Sco C |radial_v={{val|−9.72|0.64}}<ref name=mr2022>{{cite journal |last1=Miret-Roig |first1=N. |last2=Galli |first2=P. A. B. |last3=Olivares |first3=J. |last4=Bouy |first4=H. |last5=Alves |first5=J. |last6=Barrado |first6=D. |title=The star formation history of Upper Scorpius and Ophiuchus. A 7D picture: Positions, kinematics, and dynamical traceback ages |journal=Astronomy and Astrophysics |date=2022 |volume=667 |doi=10.1051/0004-6361/202244709 |arxiv=2209.12938 |bibcode=2022A&A...667A.163M }}</ref> |prop_mo_ra=−11.853<ref name=dr3c/> |prop_mo_dec=−24.920<ref name=dr3c/> |parallax=7.2608 |p_error=0.0348 |parallax_footnote=<ref name=dr3c>{{cite Gaia DR3|6245698187231874816}}</ref> |absmag_v=+0.754<ref name=freund2018>{{cite journal |last1=Freund |first1=S. |last2=Robrade |first2=J. |last3=Schneider |first3=P. C. |last4=Schmitt |first4=J. H. M. M. |title=The stellar content of the XMM-Newton slew survey |journal=Astronomy and Astrophysics |date=2018 |volume=614 |pages=A125 |doi=10.1051/0004-6361/201732009 |arxiv=1712.07410 |bibcode=2018A&A...614A.125F }}</ref> }} {{Starbox astrometry|no_heading=y |component1=ν Sco D |radial_v=−3.0<ref name=duflot1995>{{cite journal |last1=Duflot |first1=M. |last2=Figon |first2=P. |last3=Meyssonnier |first3=N. |title=Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue |journal=Astronomy and Astrophysics Supplement Series |date=1995 |volume=114 |page=269 |bibcode=1995A&AS..114..269D }}</ref> |prop_mo_ra=−7.099<ref name=dr3d/> |prop_mo_dec=−22.792<ref name=dr3d/> |parallax=7.1732 |p_error=0.01399 |parallax_footnote=<ref name=dr3d>{{cite Gaia DR3|6245698565188996992}}</ref> }} {{Starbox orbit |reference=<ref name=Levato/> |primary=ν Sco Aa |name=ν Sco Ab |period_unitless={{val|fmt=none|5.55206|0.00003|u=days}} |periastron={{val|fmt=none|2442185.555|0.349}} |k1={{val|26.5|1.3}} |eccentricity={{val|0.11|0.05}} |periarg={{val|267|23}} }} {{Starbox orbit |reference=<ref name=msc/> |primary=ν Sco Aab |name=ν Sco Ac |period=10.0611 |axis_unitless = {{val|0.073|ul=AU}} |periastron={{val|fmt=none|2014.987}} |eccentricity=0.92 |inclination=89.7 |node=346.4 |periarg=118.9 }} {{Starbox orbit |reference=<ref name=msc/> |primary=ν Sco A |name=ν Sco B |period=500 |axis_unitless = {{val|1.126|ul=AU}} |periastron={{val|fmt=none|1672}} |eccentricity=0.5 |inclination=91.2 |node=0.9 |periarg=125.0 }} {{Starbox detail |source= |component1 = Aa |mass = {{Val|5.1|0.3|0.2}}<ref name=DR3a/> |radius={{Val|6.52|0.24|0.23}}<ref name=DR3a>{{cite DR3|6245697981070158080}}</ref> |luminosity={{Val|1260|250|160|fmt=commas}}<ref name=DR3a/> |temperature={{Val|13400|900|550|fmt=commas}}<ref name=DR3a/> |gravity={{Val|3.48|0.04}}<ref name=DR3a/> |metal_fe=0.58<ref name=DR3a/> |component2 = Ab |mass2 = 2.28<ref name=msc>{{Cite journal | last=Tokovinin | first=Andrei | date=March 2018 | title=The Updated Multiple Star Catalog | journal=The Astrophysical Journal Supplement Series | volume=235 | issue=1 | pages=6 | doi=10.3847/1538-4365/aaa1a5 | issn=0067-0049 | arxiv=1712.04750 | bibcode=2018ApJS..235....6T | s2cid=119047709 | doi-access=free }}</ref>
}} {{Starbox detail|no_heading=y |component1 = Ac |mass = 2.46<ref name=msc/> |component2 = B |mass2 = 3.79<ref name=msc/> }} {{Starbox detail|no_heading=y |component1 = C |mass = {{Val|3.473|0.001|0.002}}<ref name=dr3c/> |temperature= {{Val|13251|6|4|fmt=commas}}<ref name=dr3c/> |luminosity={{Val|154|7|2}}<ref name=dr3c/> |radius={{Val|2.378|0.010}}<ref name=dr3c/> |gravity={{Val|4.247|0.009}}<ref name=dr3c/> |metal_fe=0.396 ± 0.007<ref name=dr3c/> |component2 = Da |mass2 = 1.96<ref name=msc/> }} {{Starbox catalog |names={{odlist |name=Jabbah |B=ν Sco |F=14 Sco |ADS=9951 |CCDM=J16120-1928 }}<ref name=Simbad>{{cite simbad |title=nu Sco |access-date=2026-04-01 }}</ref> |component1=ν Sco AB |names1={{odlist |BD=−19°4333 |HD=145502 |HIP=79374 |HR=6027 |SAO=159764 }}<ref name=SimbadA>{{cite simbad|title=nu Sco A|access-date=1 April 2026}}</ref><ref name=SimbadB>{{cite simbad|title=nu Sco B|access-date=1 April 2026}}</ref> |component2=ν Sco CD |names2={{odlist |BD=−19°4332 |HD=145501 |HR=6026 |SAO=159763 }}<ref name=SimbadC>{{cite simbad|title=nu Sco C|access-date=1 April 2026}}</ref><ref name=SimbadD>{{cite simbad|title=nu Sco D|access-date=1 April 2026}}</ref> }} {{Starbox reference |Simbad=nu+Sco|sn=ν Sco |Simbad2=nu+Sco+A|sn2=ν Sco A |Simbad3=nu+Sco+B|sn3=ν Sco B |Simbad4=nu+Sco+C|sn4=ν Sco C |Simbad5=nu+Sco+D|sn5=ν Sco D }} {{Starbox end}} '''Nu Scorpii''' ('''ν Scorpii''', abbreviated '''Nu Sco''', '''ν Sco''') is a multiple star system in the constellation of Scorpius. It is most likely a septuple star system,<ref name=msc/> consisting of two close groups (designated Nu Scorpii AB and CD) that are separated by 41 arcseconds.<ref name=msc/> Based on parallax measurements,<ref name=HIP/> it is approximately 470 light-years from the Sun.
The component Nu Scorpii Aa is formally named '''Jabbah''' {{IPAc-en|'|dZ|æ|b|@}}.<ref name="IAU-LSN">{{cite web | url=https://www.iau.org/public/themes/naming_stars/ | title=Naming Stars |publisher=IAU.org |access-date=16 December 2017}}{{dead link|date=April 2026}}</ref>
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==Location== [[File:Rho Ophiucus Widefield.jpg|thumb|left|The ρ Ophiuchi region. ν is embedded in the Blue Horsehead nebula near the bottom of the frame (north is down).]] Nu Scorpii is the system that causes the reflection nebula cataloged as IC 4592 and known as the Blue Horsehead nebula. Reflection nebulae are actually made up of very fine dust that normally appears dark but can look quite blue when reflecting the light of energetic nearby stars.<ref>{{cite web|url=http://wise.ssl.berkeley.edu/gallery_ic4592.html|date=22 November 2011|title=WISE - Multimedia Gallery: IC 4592|work=WISE: Wide-Field Infrared Survey Explorer|access-date=24 February 2017}}</ref>
Since it is near the ecliptic, Nu Scorpii can be occulted by the Moon and, very rarely, by planets. Mercury occulted it on 14 December 1821, but will not occult it again until 2 December 2031. The last occultation by Venus took place on 27 December 1852 and the next will take place on 30 December 2095. On 29 July 1808 there was an occultation by Neptune.{{citation needed|date=February 2017}} {{clear left}}
==Nomenclature== ''ν Scorpii'' (Latinised to ''Nu Scorpii'') is the system's Bayer designation. The designations of its two constituent groups as ''Nu Scorpii AB'' and ''CD''; of the component ''Nu Scorpii Aa'', and of other components similarly lettered, derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU).<ref name="planetnaming">{{cite arXiv |title=On the naming convention used for multiple star systems and extrasolar planets |date=2010 |eprint=1012.0707 |class=astro-ph.SR |last1= Hessman |first1=F. V. |last2= Dhillon |first2=V. S. |last3= Winget |first3=D. E. |last4= Schreiber |first4=M. R. |last5= Horne |first5=K. |last6= Marsh |first6=T. R. |last7= Guenther |first7=E. |last8= Schwope |first8=A. |last9= Heber |first9=U. }}</ref>
[[File:Jabbah Nu Scorpii Aa WISE.jpg|thumb|left|Constellation of Scorpius surrounding Jabbah, seen in infrared by NASA's WISE telescope]]
Nu Scorpii bore the traditional name ''Jabbah'', possibly from the Arabic ''Iklīl al Jabhah'' (إكليل الجبهة 'the crown of the forehead').<ref name=Kaler>{{cite web |title=Jabbah |first=Jim|last=Kaler |url=http://stars.astro.illinois.edu/sow/jabbah.html |access-date=2017-01-29}}</ref><ref name=Allen>{{cite web |title=Star Names — Their Lore and Meaning: Scorpio |first=Richard Hinckley|last=Allen |url=https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Scorpio*.html |access-date=2017-01-29}}</ref> In 2016, the IAU organized a Working Group on Star Names (WGSN)<ref name="WGSN">{{cite web | url=https://www.iau.org/science/scientific_bodies/working_groups/280/ | title=IAU Working Group on Star Names (WGSN)|access-date=22 May 2016}}</ref> to catalog and standardize proper names for stars. The WGSN decided to attribute proper names to individual stars rather than entire multiple systems.<ref name="TriRpt18">{{cite web | url=https://www.iau.org/static/science/scientific_bodies/working_groups/280/wg-starnames-triennial-report-2015-2018.pdf | page=5 | title=WG Triennial Report (2015-2018) - Star Names |access-date=2018-07-14}}</ref> It approved the name ''Jabbah'' for the component Nu Scorpii Aa on 30 June 2017 and it is now so included in the List of IAU-approved Star Names.<ref name="IAU-LSN"/>
In Chinese astronomy, Nu Scorpii is called 鍵閉, Pinyin: Jiànbì, meaning ''Door Bolt'', because it is marking itself and standing alone in the ''Door Bolt'' asterism, Room mansion (see : Chinese constellations).<ref>{{in lang|zh}} [http://aeea.nmns.edu.tw/2006/0605/ap060508.html AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 8 日] {{Webarchive|url=https://web.archive.org/web/20200113040500/http://aeea.nmns.edu.tw/2006/0605/ap060508.html |date=2020-01-13 }}</ref> 鍵閉 (Jiànbì), westernized into ''Keen Pi'', but that name (meaning "the Two Parts of a Lock") was ascribed to the pair Lambda Scorpii (Shaula) and Upsilon Scorpii (Lesath) by R.H. Allen.<ref name=Allen/> {{clear left}}
==Multiplicity== <div style="float:left; width:230px; border:solid black 1px; text-align: center; margin: 4px 12px 12px 0px; padding: 4px; font-size: 90%;"> {{tree chart/start}} {{tree chart|border=1| | | | |, |S1| |S1='''Aa''' }} {{tree chart|border=0| | | |, |( |PA| |PA=Period = 5.55d<br/>a = 1.06 mas }} {{tree chart|border=1| | | |! |` |S2| |S2='''Ab''' }} {{tree chart|border=0| | |, |( |PB| | |PB=Period = 5.7y<br/>a = 63 mas }} {{tree chart|border=1| | |! |` |S3| | |S3='''Ac''' }} {{tree chart|border=0| |,|( |PC| | | |PC=1.3″ separation }} {{tree chart|border=1| |!|` |S4| | | |S4='''B''' }} {{tree chart|border=0| |(| |PD| | | |PD=41.1″ separation }} {{tree chart|border=1| |!|, |S5| | | |S5='''C''' }} {{tree chart|border=0| |`|( |PE| | | |PE=2″ separation }} {{tree chart|border=1| | |! |, |S6| | |S6='''Da''' }} {{tree chart|border=0| | |` |( |PE| | |PE=''Orbit unknown'' }} {{tree chart|border=1| | | |` |S7| | |S7='''Db''' }} {{tree chart/end}} Hierarchy of orbits in the ν Scorpii system </div>
thumb|left|Schematic of the Nu Scorpii system (not to scale) Nu Scorpii is a septuple star system.<ref name=msc/> It is one of only two such known systems, the other being AR Cassiopeiae.{{cn|date=April 2026}} Higher-multiplicity star systems are uncommon because they are less stable than their simpler counterparts, and often decay into smaller systems.
Nu Scorpii is split into two groups, Nu Scorpii AB and Nu Scorpii CD. Nu Scorpii CD is located 41 arcseconds away from Nu Scorpii A, and is also known as HR 6026.<ref name=SimbadC/> Nu Scorpii AB and CD cannot be resolved using the naked eye, but can be resolved using a telescope.<ref>{{cite simbad|title=* nu. Sco|access-date=24 February 2017}}</ref>
===Nu Scorpii A=== Nu Scorpii A is the brightest member of the system. It has an apparent magnitude from 4.35, meaning that it can be seen with the naked eye.
Nu Scorpii A is itself a triple star system. The inner pair is known as Nu Scorpii Aab, and it is a single-lined spectroscopic binary. Its components cannot be resolved but the stars' movements cause periodic Doppler shifts in their spectra. "Single-lined" means that light from only one of the stars can be detected. The pair has an orbital period of 5.5521 days and an eccentricity of 0.11, and an estimated separation of about 1.057 milliarcseconds.<ref name=Levato>{{cite journal|title=Stellar multiplicity in the Scorpius-Centaurus association|author1=Levato, H.|author2=Malaroda, S.|author3=Morrell, N.|author4=Solivella, G.|journal=Astrophysical Journal Supplement Series|volume=64|pages=487–503|date=1987|bibcode=1987ApJS...64..487L|doi=10.1086/191204}}</ref> The brighter component, Nu Scorpii Aa, has a spectral type of B3V implying a B-type main sequence star. The fainter component, Nu Scorpii Ab, is thought to have an apparent magnitude of 6.90.<ref name=msc/>
The outer star, Nu Scorpii Ac, is 63 milliarcseconds away from the inner pair and it has an apparent magnitude of 6.62.<ref name=msc/>
===Nu Scorpii B=== Nu Scorpii B is part of the Nu Scorpii AB sub-system and orbits the three Nu Scorpii A stars. Nu Scorpii A and B are separated by 1.305 arcseconds; this translates to an orbital period of over 452 years, so no orbital motion has been detected. It has an apparent magnitude of 5.40, but its spectral type is unknown.<ref name=msc/>
===Nu Scorpii CD=== Nu Scorpii CD is also a triple star system. The primary component of the system, Nu Scorpii C, is a late B-type main sequence star with a spectral type of B8V. With an apparent magnitude of 6.90, it outshines its fainter companion, Nu Scorpii D, which only has an apparent magnitude of 7.39. The two are separated by about 2 arcseconds.<ref name=msc/>
Nu Scorpii D, with an apparent magnitude of 7.39, is the faintest component of the Nu Scorpii system and has a spectral class of B9V. It is one of a class of chemically peculiar stars known as Ap/Bp stars; in particular, it has strong silicon emission lines. It too is likely also another spectroscopic binary: Nu Scorpii Da is another late B star, similar to Nu Scorpii C, but very little is known about Nu Scorpii Db.<ref>{{cite journal|title=Radial velocities of bright southern stars. I - 139 B-type HR and FK stars|author1=Andersen, J.|author2=Nordstrom, B.|journal=Astronomy and Astrophysics Supplement Series|volume=52|pages=471–482|date=1983|bibcode=1983A&AS...52..471A}}</ref>
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==References== {{Reflist}}
==External links== *{{APOD |date=8 August 2006 |title=Image of Nu Scorpii}}
{{Stars of Scorpius}}
Scorpii, Nu Category:B-type main-sequence stars Category:B-type subgiants 7 Category:Scorpius Category:Spectroscopic binaries Jabbah Scorpii, 14 079374 6026 7 145501 2 Category:Durchmusterung objects