View source for Delta Apodis

{{Short description|Double star in the constellation Apus}}
{{Starbox begin
 | name=δ Apodis
}}
{{Starbox image
 | image=
  {{Location mark
    | image=Apus constellation map.svg
    | alt= | float=center | width=240
    | label= | position=right
    | mark=Red circle.svg | mark_width=10 | mark_link=δ Apodis
    | x%=46.0 | y%=64.0
  }}
 | caption=Location of δ Apodis (circled)
}}
{{Starbox observe 2s
 | epoch       = J2000
 | constell    = [[Apus]]<ref name=Anderson_Francis_2012/>
 | component1  = δ<sup>1</sup> Aps
 | ra1         = {{RA|16|20|20.802}}<ref name=GaiaDR3a/>
 | dec1        = {{DEC|-78|41|44.69}}<ref name=GaiaDR3a/>
 | appmag_v1   = {{val|4.66|to|4.87}}<ref name=gcvs/>
 | component2  = δ<sup>2</sup> Aps
 | ra2         = {{RA|16|20|26.858}}<ref name=GaiaDR3b3/>
 | dec2        = {{DEC|-78|40|02.99}}<ref name=GaiaDR3b3/>
 | appmag_v2   = +5.27<ref name=clpl4_99/>
}}
{{Starbox character
 | component1  = δ<sup>1</sup> Aps
 | class       = M5&nbsp;IIIb<ref name=houk1979/>
 | b-v         = +1.69<ref name=clpl4_99/>
 | u-b         = +1.680{{±|0.110}}<ref name=Anderson_Francis_2012/>
 | variable    = [[slow irregular variable|LB]]?<ref name=gcvs/>
 | component2  = δ<sup>2</sup> Aps
 | class2      = K3&nbsp;III<ref name=houk1979/>
 | b-v2        = +1.413{{±|0.012}}<ref name=Anderson_Francis_2012/>
 | u-b2        = +1.62<ref name=clpl4_99/>
}}
{{Starbox astrometry
 | component1  = δ<sup>1</sup> Aps
 | radial_v    = −12.0<ref name=scfs/>
 | prop_mo_ra  = −9.678
 | prop_mo_dec = −37.147
 | pm_footnote = <ref name=GaiaDR3a/>
 | parallax    = 5.2508 
 | p_error     = 0.1942
 | parallax_footnote = <ref name=GaiaDR3a/>
 | absmag_v    = −2.16<ref name=Anderson_Francis_2012/>
 | component2  = δ<sup>2</sup> Aps
 | radial_v2   = −10.2<ref name=gcsrv/>
 | prop_mo_ra2 = −1.817
 | prop_mo_dec2= −31.511
 | pm_footnote2 = <ref name=GaiaDR3a/>
 | parallax2   = 5.795
 | p_error2    = 0.0902
 | parallax_footnote2 = <ref name=GaiaDR3a/>
 | absmag_v2   = −1.10<ref name=Anderson_Francis_2012/>
}}
<!--
{{Starbox detail
 | mass=
 | radius=
 | luminosity=
 | temperature=
 | metal_fe=
 | rotational_velocity=
 | age_gyr=
 | luminosity2 = 557.18<ref name=Anderson_Francis_2012/>
}}
-->
{{Starbox catalog
 | names = {{odlist | CP=−78&nbsp;1092 | FK5=1424 | HR=6020 }}<ref name=SIMBAD1/><ref name=SIMBAD2/>
 | component1 = δ<sup>1</sup> Aps
 | names1     = {{odlist | HD=145366 | HIP=80047 | SAO=257380 }}<ref name=SIMBAD1/>
 | component2 = δ<sup>2</sup> Aps
 | names2     = {{odlist | HD=145388 | HIP=80057 | SAO=257381 }}<ref name=SIMBAD2/>
}}
{{Starbox reference
 | Simbad = del01+Aps | sn=δ<sup>1</sup> Aps
 | Simbad2 = del02+Aps | sn2=δ<sup>2</sup> Aps
}}
{{Starbox end}}
'''Delta Apodis''' is a [[double star]] in the southern [[constellation]] of [[Apus]]. Its identifier is a [[Bayer designation]] that is [[Romanization of Greek|Latinized]] from δ Apodis, and abbreviated Del Aps or δ Aps, respectively. Based on [[stellar parallax|parallax]] measurements, the distance to δ{{sup|1}} Apodis is approximately 620&nbsp;[[light years]],<ref name=GaiaDR3a/> while δ{{sup|2}} Apodis is found to be around 563&nbsp;[[light years]] from [[Earth]].<ref name=GaiaDR3b3/> They may form a [[common proper motion]] pair.{{cn|date=March 2025}}

[[File:Delta1ApsLightCurve.png|thumb|left|A [[light curve]] for Delta<sup>1</sup> Apodis, plotted from ''[[Hipparcos]]'' data<ref name="CDS"/>]]
The brighter star, '''δ{{sup|1}} Apodis''', has an [[apparent magnitude]] that varies from +4.66 to +4.87.<ref name=AAVSOdel1/> It is a [[red giant]] with a [[stellar classification]] of M5 IIIb,<ref name=houk1979/> and is classified as a [[semiregular variable]] with pulsations of multiple periods of 68.0, 94.9 and 101.7 days.<ref name=mnras400_4_1945/> '''δ{{sup|2}} Apodis''' has an [[apparent magnitude]] of +5.27 and is an orange [[stellar classification|K-type]] [[giant star|giant]] with a class of K3&nbsp;III.<ref name=houk1979/> Both stars are bright enough to be seen with the [[naked eye]] under good observing conditions. The pair have an [[angular separation]] of 103.4&nbsp;[[arcsecond]]s (as of 2016),<ref name=Mason_et_al_2014/> which is wide enough to allow them to be seen individually by a person with good eyesight.

==Naming==
In [[Chinese language|Chinese]] caused by adaptation of the European southern hemisphere constellations into the Chinese system, {{lang|zh|異雀}} ({{lang|zh-Latn|Yì Què}}), meaning ''[[Chinese constellations#The Southern Asterisms|Exotic Bird]]'', refers to an asterism consisting of δ<sup>1</sup> Apodis, [[Zeta Apodis|ζ Apodis]], [[Iota Apodis|ι Apodis]], [[Beta Apodis|β Apodis]], [[Gamma Apodis|γ Apodis]], [[Delta Octantis|δ Octantis]], [[Eta Apodis|η Apodis]], [[Alpha Apodis|α Apodis]] and [[Epsilon Apodis|ε Apodis]]. Consequently, δ<sup>1</sup> Apodis itself is known as {{lang|zh|異雀六}} ({{lang|zh-Latn|Yì Què liù}}, {{langx|en|the Sixth Star of Exotic Bird}}.)<ref>{{in lang|zh}} [http://aeea.nmns.edu.tw/2006/0607/ap060729.html AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 29 日] {{Webarchive|url=https://web.archive.org/web/20110522124325/http://aeea.nmns.edu.tw/2006/0607/ap060729.html |date=2011-05-22 }}</ref>

==References==
{{reflist|refs=

<ref name=GaiaDR3a>{{cite Gaia DR3|5778842011026728704}}</ref>

<ref name=GaiaDR3b3>{{cite Gaia DR3|5778842423342242048}}</ref>

<ref name=gcvs>{{cite journal|bibcode=2009yCat....102025S|title=VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)|journal=VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S|volume=1|pages=B/gcvs|display-authors=etal|last1=Samus|first1=N. N.|last2=Durlevich|first2=O. V.|year=2009}}</ref>

<ref name="CDS">{{cite web
 | url=https://cdsarc.cds.unistra.fr/viz-bin/ftp-index?/ftp/cats/more/HIP/cdroms/cats
 | website=Centre de Données astronomiques de Strasbourg | title=/ftp/cats/more/HIP/cdroms/cats
 | publisher=Strasbourg astronomical Data Center |access-date=15 October 2022}}</ref>

<ref name=houk1979>{{citation | title=Michigan catalogue of two-dimensional spectral types for the HD stars | volume=1 | last1=Houk | first1=Nancy | location=Ann Arbor, Michigan | publisher=Dept. of Astronomy, University of Michigan | year=1979 | bibcode=1978mcts.book.....H | postscript=. }}</ref>

<ref name=scfs>{{citation | display-authors=1 | title=Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions | last1=Wielen | first1=R. | last2=Schwan | first2=H. | last3=Dettbarn | first3=C. | last4=Lenhardt | first4=H. | last5=Jahreiß | first5=H. | last6=Jährling | first6=R. | journal=Veroeffentlichungen des Astronomischen Rechen-Instituts Heidelberg | publisher=Astronomisches Rechen-Institut Heidelberg | issue=35 | year=1999 | volume=35 | page=1 | bibcode=1999VeARI..35....1W | postscript=. }}</ref>

<ref name=clpl4_99>{{citation | display-authors=1 | last1=Johnson | first1=H. L. | last2=Iriarte | first2=B. | last3=Mitchell | first3=R. I. | last4=Wisniewskj | first4=W. Z. | title=UBVRIJKL photometry of the bright stars | journal=Communications of the Lunar and Planetary Laboratory | volume=4 | issue=99 | year=1966 | page=99 | bibcode=1966CoLPL...4...99J | postscript=. }}</ref>

<ref name=mnras400_4_1945>{{citation | display-authors=1 | last1=Tabur | first1=V. | last2=Bedding | first2=T. R. | last3=Kiss | first3=L. L. | last4=Moon | first4=T. T. | last5=Szeidl | first5=B. | last6=Kjeldsen | first6=H. | title=Long-term photometry and periods for 261 nearby pulsating M giants | journal=[[Monthly Notices of the Royal Astronomical Society]] | volume=400 | issue=4 | pages=1945–1961 |date=December 2009 | doi=10.1111/j.1365-2966.2009.15588.x | doi-access=free | bibcode=2009MNRAS.400.1945T | postscript=. |arxiv = 0908.3228 | s2cid=15358380 }}</ref>

<ref name=SIMBAD1>{{citation | title=del01 Aps -- Pulsating variable Star | work=SIMBAD | publisher=[[Centre de Données astronomiques de Strasbourg]] | url=http://simbad.u-strasbg.fr/simbad/sim-id?Ident=HD+145366 | accessdate=2012-07-08 | postscript=. }}</ref>

<ref name=SIMBAD2>{{citation | title=HR 6021 -- Star in double system | work=SIMBAD | publisher=Centre de Données astronomiques de Strasbourg | url=http://simbad.u-strasbg.fr/simbad/sim-id?Ident=del02+Aps | accessdate=2012-07-08 | postscript=. }}</ref>

<ref name=gcsrv>{{citation | last=Wilson | first=Ralph Elmer | year=1953 | title=General Catalogue of Stellar Radial Velocities | journal=Carnegie Institute Washington D.C. Publication | publisher=[[Carnegie Institution of Washington]] | location=Washington | bibcode=1953GCRV..C......0W | postscript=. }}</ref>

<ref name=AAVSOdel1>{{citation | postscript=.
 | title=Delta1 Apodis
 | last=Watson | first=Christopher |date=August 25, 2009
 | work=The International Variable Star Index
 | publisher=[[American Association of Variable Star Observers]]
 | url=http://www.aavso.org/vsx/index.php?view=detail.top&oid=842
 | accessdate=30 March 2016}}</ref>

<ref name=Anderson_Francis_2012>{{citation
 | last1=Anderson | first1=E. | last2=Francis | first2=Ch.
 | title=XHIP: An extended hipparcos compilation
 | journal=Astronomy Letters
 | volume=38 | issue=5 | pages=331 | year=2012
 | bibcode=2012AstL...38..331A | arxiv=1108.4971
 | doi=10.1134/S1063773712050015 | s2cid=119257644 | postscript=. }}</ref>

<ref name=Mason_et_al_2014>{{citation
 | title=The Washington Visual Double Star Catalog
 | display-authors=1 | last1=Mason | first1=B. D.
 | last2=Wycoff | first2=G. L. | last3=Hartkopf | first3=W. I.
 | last4=Douglass | first4=G. G. | last5=Worley | first5=C. E.
 | journal=The Astronomical Journal
 | volume=122 | issue=6 | pages=3466–3471 | year=2014
 | bibcode=2001AJ....122.3466M | postscript=.
 | doi=10.1086/323920 | doi-access=free }}</ref>

}}

==External links==
* [http://aladin.u-strasbg.fr/AladinPreview?-c=V*+del01+Aps&ident=V*+del01+Aps&submit=Aladin+previewer Image δ Apodis]

{{Stars of Apus}}

{{DEFAULTSORT:Delta Apodis}}
[[Category:M-type giants]]
[[Category:K-type giants]]
[[Category:Semiregular variable stars]]
[[Category:Double stars]]
[[Category:Apus]]
[[Category:Bayer objects|Apodis, Delta]]
[[Category:Bright Star Catalogue objects|6020]]
[[Category:Durchmusterung objects]]
[[Category:Henry Draper Catalogue objects|145366]]
[[Category:Hipparcos objects|080047 57]]
[[Category:Gould objects|Apodis, 40/1]]