| 释义 |
- Description
- Variability
- Companion
- Planet X
- References
{{Starbox begin
| name = W Aquilae
|caption=
}}{{Starbox image
| image=
| caption=W Aquilae showing the close companion
| credit=Hubble Legacy Archive
}}{{Starbox observe
| epoch=J2000
| ra={{RA|19|15|23.347}}[1]
| dec={{DEC|07|02|50.35}}[1]
| appmag_v=(A):7.0 - 14.6[3]
(B):14.8[4]
| constell=Aquila
}}{{Starbox character
| component=A
| class=S66e[5] {{nowrap|(S39e - S69e[3])}}
| b-v=+2.58[1]
| u-b=
| variable=Mira[3]
}}{{Starbox character|no_heading=y
| component=B
| class=F8/9[5]
| b-v=
| u-b=
| variable=
}}{{Starbox astrometry
| radial_v=−18.0[10]
| prop_mo_ra=
| prop_mo_dec=
| parallax=
| p_error=
| parallax_footnote=
| dist_pc=400[5]
| dist_ly=
| absmag_v=(A): −0.7 to +6.9[4]
(B):+7.1[4]
}}{{Starbox detail
| component1=A
| mass=1.04 - 3[5]
| radius=430 - 473[15] (870[1])
| luminosity={{nowrap|9,740 - 28,885[4]}}
| temperature=2,250 - 3,175[15] (1,800[1])
| metal=
| rotation=
| gravity=
| component2=B
| mass2=1.04 - 1.09[5]
| temperature2=5,900 - 6,170[5]
| age2=
}}{{Starbox catalog
| names = W Aql, IRAS 19126-0708, TYC 5142-2895-1, 2MASS J19152335-0702503, AAVSO 1910-07
}}{{ Starbox reference
| Simbad = W+Aquilae
}}{{Starbox end}}W Aquilae (W Aql / SAO 143184 / GC 2525) is a variable star in the constellation of Aquila. Its distance from the solar system is estimated between 1,100 and 7,502 light-years. DescriptionW Aquilae is an S-type star with a spectral type of S39e to S69e, a red giant similar to M-type stars, but in which the dominant spectrum oxides are formed by metals of the fifth period of the periodic table. W Aquilae is also rich in the element technetium. Another feature of this class of stars is the stellar mass loss, in the case of W Aquilae is estimated at ~ {{val|4e-7}} solar masses per year. Its effective temperature varies between 2,250 and 3,175 K and its diameter between 430 and 473 solar radii. It is also a very luminous star, between 9,740 and 28,885 times more than the sun. VariabilityW Aquilae is a variable whose brightness oscillates between magnitude +7.3 and +14.3 over a period of 490.43 days. In Mira variables (which are named after Mira, the prototype), this instability comes from pulsation in the stellar surface, causing changes in color and brightness. W Aquilae, a Mira variable, shows silicon monoxide maser emission. CompanionA magnitude 14.8 companion has been detected 0.47" SW of W Aquilae. This is fainter than W Aquilae at minimum and corresponds to an absolute magnitude of +7.1. Although that absolute magnitude would correspond to a K4 main sequence star, a spectrum was classified as F5 or F8. The separation between the two stars is 160 AU.[4] Planet XA 2014 study of W Aquilae and α Centauri with the ALMA array claimed to have accidentally detected a previously-unknown solar system object. This received widespread press coverage as a potential discovery of planet X. The paper was withdrawn without being accepted for peer-reviewed publication. References1. ^1 {{cite journal|bibcode=2009A&A...499..515R| title = Circumstellar molecular line emission from S-type AGB stars: mass-loss rates and SiO abundances| year = 2009| journal = Astronomy and Astrophysics| volume = 499| pages = 515| number = 2| id = 515-527 | author1 = Ramstedt| first1 = S.| last2 = Schöier| first2 = F. L.| last3 = Olofsson| first3 = H.| doi = 10.1051/0004-6361/200911730|arxiv = 0903.1672 }}
2. ^1 2 3 {{cite journal|bibcode= 2000A&A...355L..27H |title= The Tycho-2 catalogue of the 2.5 million brightest stars |journal= Astronomy and Astrophysics |volume= 355 |pages= L27 |author1= Høg |first1= E. |last2= Fabricius |first2= C. |last3= Makarov |first3= V. V. |last4= Urban |first4= S. |last5= Corbin |first5= T. |last6= Wycoff |first6= G. |last7= Bastian |first7= U. |last8= Schwekendiek |first8= P. |last9= Wicenec |first9= A. |year= 2000 |doi=10.1888/0333750888/2862|isbn= 0333750888 }}
3. ^1 2 3 {{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|display-authors=etal|author1=Samus|first1=N. N.|last2=Durlevich|first2=O. V.|year=2009}}
4. ^1 {{cite journal|bibcode=1953GCRV..C......0W|title=General catalogue of stellar radial velocities|journal=Washington|author1=Wilson|first1=Ralph Elmer|year=1953}}
5. ^1 2 3 4 5 6 {{cite journal|bibcode=2015A&A...574A..23D|arxiv=1501.00863|title=Classifying the secondary component of the binary star W Aquilae|journal=Astronomy & Astrophysics|volume=574|pages=A23|author1=Danilovich|first1=T.|last2=Olofsson|first2=G.|last3=Black|first3=J. H.|last4=Justtanont|first4=K.|last5=Olofsson|first5=H.|year=2015|doi=10.1051/0004-6361/201423672}}
6. ^1 2 3 4 5 {{cite journal|bibcode=2013A&A...549A..69M|arxiv=1211.3595|title=Large-scale environments of binary AGB stars probed by Herschel. I. Morphology statistics and case studies of R Aquarii and W Aquilae|journal=Astronomy & Astrophysics|volume=549|pages=A69|author1=Mayer|first1=A.|last2=Jorissen|first2=A.|last3=Kerschbaum|first3=F.|last4=Ottensamer|first4=R.|last5=Nowotny|first5=W.|last6=Cox|first6=N. L. J.|last7=Aringer|first7=B.|last8=Blommaert|first8=J. A. D. L.|last9=Decin|first9=L.|last10=Van Eck|first10=S.|last11=Gail|first11=H.-P.|last12=Groenewegen|first12=M. A. T.|last13=Kornfeld|first13=K.|last14=Mecina|first14=M.|last15=Posch|first15=Thomas|last16=Vandenbussche|first16=B.|last17=Waelkens|first17=C.|year=2013|doi=10.1051/0004-6361/201219259}}
7. ^1 2 {{cite journal|bibcode=2004ApJ...611..466T|title=Mid-Infrared Interferometry on Dust Shells around Four Late-Type Stars|journal=The Astrophysical Journal|volume=611|pages=466|author1=Tevousjan|first1=S.|last2=Abdeli|first2=K.-S.|last3=Weiner|first3=J.|last4=Hale|first4=D. D. S.|last5=Townes|first5=C. H.|year=2004|doi=10.1086/421990}}
[2][3][4][5][6][7]
}}{{Stars of Aquila}} 9 : S-type stars|Mira variables|Aquila (constellation)|Objects with variable star designations|2MASS objects|IRAS catalogue objects|Binary stars|F-type stars|Emission-line stars |