View source for Astronomy:Nu1 Sagittarii

{{short description|Triple star system in the constellation Sagittarius}}
{{DISPLAYTITLE:Nu<sup>1</sup> Sagittarii}}
{{other stars by Bayer designation|Nu Sagittarii{{!}}ν Sagittarii}}
{{Starbox begin
 | name = Nu<sup>1</sup> Sagittarii
}}
{{Starbox image
 | image = 
     <div style="position: relative">[[File:Sagittarius IAU.svg|250px|alt=Diagram showing star positions and boundaries of the Sagittarius constellation and its surroundings]]
     <div style="position: absolute; left: 50.3%; top: 33.3%;">[[File:Cercle rouge 100%.svg|12px]]</div>
     </div>
 | caption = Location of ν<sup>1</sup> Sagittarii (circled)
}}
{{Starbox observe
 | epoch = [[Astronomy:J2000.0|J2000.0]]
 | equinox = [[Astronomy:J2000.0|J2000.0]] ([[Astronomy:International Celestial Reference System|ICRS]])
 | constell = [[Astronomy:Sagittarius (constellation)|Sagittarius]]
 | ra = {{RA|18|54|10.17695}}<ref name=vanLeeuwen2007/>
 | dec = {{DEC|−22|44|41.4247}}<ref name=vanLeeuwen2007/>
 | appmag_v = +4.86<ref name=Lutz1977/>
}}
{{Starbox character
 | class = {{nowrap|G2/K1 Ib/II + B9.2p}}<ref name=parsons1998/>
 | b-v = +1.43<ref name=Lutz1977/>
 | u-b = +1.34<ref name=Lutz1977/>
 | variable = 
}}
{{Starbox astrometry
 | radial_v = −11.57<ref name=dr2/>
 | prop_mo_ra = +4.291<ref name=dr2/>
 | prop_mo_dec = −7.786<ref name=dr2/>
 | parallax = 2.3170
 | p_error = 0.2139
 | parallax_footnote = <ref name=dr2/>
 | absmag_v = −3.91<ref name=Cardini2005/>
}}
{{Starbox detail
 | source = 
 | mass = 
 | radius = 101<ref name=dr2/>
 | luminosity = 3,464<ref name=dr2/>
 | temperature = 4,401<ref name=dr2/>
 | gravity = 
 | metal_fe = 
 | rotational_velocity = 
 | age_gyr = 
}}
{{Starbox catalog
 | names = {{odlist | name=Ainalrami | B=ν<sup>1</sup>&nbsp;Sgr | F=32&nbsp;Sgr | BD=−22°4907 | HD=174974 | HIP=92761 | HR=7116 | SAO=187426 | WDS=J18542-2245 }}<ref name=SIMBAD/>
}}
{{Starbox reference
 | Simbad = nu.01+Sgr
}}
{{Starbox end}}

'''Nu<sup>1</sup> Sagittarii''' ('''ν<sup>1</sup>&nbsp;Sagittarii''', abbreviated '''Nu<small><sup>1</sup></small> Sgr''', '''ν<sup>1</sup> Sgr''') is a [[Astronomy:Star system#Triple star systems|triple star system]]<ref name=Eggleton2008/> about 1,100 [[Astronomy:Light-year|light-year]]s from [[Astronomy:Earth|Earth]]. Its three components are designated Nu<sup>1</sup> Sagittarii A (officially named '''Ainalrami''' {{IPAc-en|E|n|@l|'|r|ei|m|i}}, the traditional name for the system),<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}}</ref> B and C.<ref name="WDS"/> A and B themselves form a [[Astronomy:Binary star#Spectroscopic binaries|spectroscopic binary]].<ref name=Eggleton2008/> The system is 0.11 degree north of the [[Astronomy:Ecliptic|ecliptic]].

== Nomenclature ==

''ν<sup>1</sup> Sagittarii'' ([[Social:Latinisation of names|Latinised]] to ''Nu<sup>1</sup> Sagittarii'') is the system's [[Astronomy:Bayer designation|Bayer designation]].

Nu<sup>1</sup> and [[Astronomy:Nu2 Sagittarii|Nu<sup>2</sup> Sagittarii]] (together designated [[Astronomy:Nu Sagittarii|Nu Sagittarii]]) bore the traditional name ''Ain al Rami'', which is from the [[Social:Arabic|Arabic]] عين الرامي  ''ʽain al-rāmī'' meaning 'eye of the archer'.<ref name=allen1899/> In 2016, the IAU organized a [[Astronomy:IAU Working Group on Star Names|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 ''Ainalrami'' for the component Nu<sup>1</sup> Sagittarii A on 5 September 2017 and it is now so included in the List of IAU-approved Star Names.<ref name="IAU-LSN"/>

Nu<sup>1</sup> and Nu<sup>2</sup> Sagittarii, together with [[Astronomy:Tau Sagittarii|Tau Sagittarii]], [[Astronomy:Psi Sagittarii|Psi Sagittarii]], [[Astronomy:Omega Sagittarii|Omega Sagittarii]], [[Astronomy:60 Sagittarii|60 Sagittarii]] and [[Astronomy:Zeta Sagittarii|Zeta Sagittarii]] were ''Al Udḥiyy'', the Ostrich's Nest.<ref name=allen1899/>

== Properties ==

Nu<sup>1</sup> Sagittarii A is a [[Astronomy:Stellar classification|spectral type]] K1 bright [[Astronomy:Giant star|giant]] which has an [[Astronomy:Apparent magnitude|apparent magnitude]] of +4.86. It is a [[Astronomy:Glossary of astronomy#M|microvariable]] with a [[Physics:Frequency|frequency]] of 0.43398 cycles per day and an [[Physics:Amplitude|amplitude]] of 0.0078 magnitude.<ref name=koen2002/> In 1982 it was found to have a hotter companion, Nu<sup>1</sup> Sagittarii B, a rapidly rotating B9 type star.<ref name=Kondo1982/> The pair [[Physics:Orbit|orbit]] with a [[Astronomy:Orbital period|period]] of around 370&nbsp;days.<ref name=Eggleton2008/> A magnitude +11.2 companion, component C,<ref name="WDS"/> is orbiting further out at an [[Astronomy:Angular distance|angular separation]] of 2.5 [[Minute and second of arc|arcseconds]] from the primary.<ref name=Eggleton2008/>

==References==
{{reflist|refs=

<ref name=allen1899>{{cite book
 | last=Allen
 | first=R. H.
 | year=1963
 | title=Star Names: Their Lore and Meaning
 | url=https://archive.org/details/starnamestheirlo00alle/page/355
 | access-date=2012-09-04
 | edition=Reprint
 | publisher=Dover Publications Inc
 | location=New York
 | isbn=0-486-21079-0
 | page=[https://archive.org/details/starnamestheirlo00alle/page/355 355]
 | url-access=registration
 }}</ref>

<ref name=Kondo1982>{{citation
 | title=The early-type component in ν¹ Sagittarii
 | display-authors=1 | last1=Kondo | first1=Y.
 | last2=McCluskey | first2=G. E. | last3=Wu | first3=C.-C.
 | journal=Publications of the Astronomical Society of the Pacific
 | volume=94 | pages=647–649 | date=August 1982 | postscript=.
 | doi=10.1086/131037 | bibcode=1982PASP...94..647K | doi-access=free }}</ref>

<ref name=Cardini2005>{{citation
 | title=Mg II chromospheric radiative loss rates in cool active and quiet stars
 | last1=Cardini | first1=D. | postscript=.
 | journal=Astronomy and Astrophysics
 | volume=430 | pages=303–311 | date=January 2005
 | doi=10.1051/0004-6361:20041440 | bibcode=2005A&A...430..303C |arxiv = astro-ph/0409683 | s2cid=12136256 }}</ref>

<ref name=koen2002>{{citation | postscript=.
 | title=New periodic variables from the Hipparcos epoch photometry
 | journal=Monthly Notices of the Royal Astronomical Society
 | last1=Koen | first1=Chris | last2=Eyer | first2=Laurent
 | volume=331 | pages=45–59 | year=2002 | issue=1
 | arxiv=astro-ph/0112194
 | doi=10.1046/j.1365-8711.2002.05150.x | bibcode=2002MNRAS.331...45K | s2cid=10505995
 }}</ref>

<ref name=Eggleton2008>{{citation
 | last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A.
 | title=A catalogue of multiplicity among bright stellar systems
 | journal=Monthly Notices of the Royal Astronomical Society
 | volume=389 | issue=2 | pages=869–879 | date=September 2008
 | bibcode=2008MNRAS.389..869E | doi=10.1111/j.1365-2966.2008.13596.x
 | arxiv=0806.2878 | s2cid=14878976 | postscript=. }}</ref>

<ref name=Lutz1977>{{citation
 | title=Spectral classification and UBV photometry of bright visual double stars
 | journal=Astronomical Journal | postscript=.
 | volume=82 | pages=431–434 |date=June 1977
 | doi=10.1086/112066 | bibcode=1977AJ.....82..431L | doi-access=free }}</ref>

<ref name=vanLeeuwen2007>{{citation
 | 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 | postscript=. }}</ref>

<ref name=parsons1998>{{citation
 | last1=Parsons | first1=Sidney B. | last2=Ake | first2=Thomas B.
 | title= Ultraviolet and Optical Studies of Binaries with Luminous Cool Primaries and Hot Companions. V. The Entire IUE Sample
 | journal=The Astrophysical Journal Supplement Series
 | volume=119 | pages=83 | year=1998 | issue=1 | postscript=.
 | bibcode= 1998ApJS..119...83P | doi= 10.1086/313152 | doi-access=free }}</ref>

<ref name=SIMBAD>{{cite simbad
 | title=nu01 Sgr | access-date=2017-07-06 | postscript=. }}</ref>

<ref name="WDS">{{cite web | url=http://ad.usno.navy.mil/wds/ | title=Washington Double Star Catalog | publisher=United States Naval Observatory | access-date=2 January 2018 | archive-url=https://web.archive.org/web/20110214155533/http://ad.usno.navy.mil/wds/ | archive-date=14 February 2011 | url-status=dead }}</ref>

<ref name=dr2>{{cite DR2|4075705783885296640}}</ref>

}}

{{Stars of Sagittarius|state=collapsed}}

{{DEFAULTSORT:Nu1 Sagittarii}}
[[Category:K-type bright giants]]
[[Category:K-type supergiants]]
[[Category:B-type stars]]
[[Category:Bayer objects|Sagittarii, Nu]]
[[Category:Sagittarius (constellation)]]
[[Category:Durchmusterung objects|BD-22 4907]]
[[Category:Flamsteed objects|Sagittarii, 32]]
[[Category:Henry Draper Catalogue objects|174974]]
[[Category:Hipparcos objects|092761]]
[[Category:Bright Star Catalogue objects|7116]]
[[Category:Spectroscopic binaries]]
[[Category:Stars with proper names|Ainalrami]]

{{Sourceattribution|Nu1 Sagittarii}}