| 词条 | R Aquarii |
| 释义 |
| name=R Aquarii }}{{Starbox image | image={{Location mark |image=Aquarius constellation map.svg|alt=|float=center|width=300 |label=|position=right |mark=Red circle.svg|mark_width=8|mark_link=R Aqr |x=112|y=592 }} |caption=Location of R Aquarii (circled) }}{{Starbox observe | epoch=J2000 | ra={{RA|23|43|49.46201}}[1] | dec={{DEC|−15|17|04.1385}}[1] | appmag_v=5.2 - 12.4[3] | constell=Aquarius }}{{Starbox character | class=M5e-M8.5e + pec[3] | b-v=+1.98[2] | u-b=−0.62[2] | variable=Mira + Z And[3] }}{{Starbox astrometry | radial_v=-22.0[4] | prop_mo_ra={{nowrap|+37.13 ± 0.47[9]}} | prop_mo_dec={{nowrap|−28.62 ± 0.44[9]}} | parallax=4.59 | p_error=0.24 | parallax_footnote = [5] | absmag_v= }}{{Starbox orbit | reference = [6] | period_unitless = 15,943 ± 471 | eccentricity = 0.25 ± 0.07 | inclination = 70 | axis = 0.071 - 0.084 | axis_unitless = 14.2 - 16.8 AU }}{{Starbox detail | component1 = A | mass=1 - 1.5[6] | radius=430[6] | luminosity=4,780[7] | temperature=2,800[7] | gravity=−0.5[7] | metal= | rotation= | component2 = B | mass2=0.6 - 1[6] | radius2= | luminosity2= | temperature2 = | metal2= | rotation2= | age2= }}{{Starbox catalog | names=R Aqr, BD−16°6352, HD 222800, HIP 117054, HR 8992, SAO 165849 }}{{Starbox reference | Simbad=HD+222800 }}{{starbox sources|HIP|CCDM|HR}}{{Starbox end}}R Aquarii (R Aqr) is a variable star in the constellation Aquarius.[8] R Aquarii is a symbiotic star believed to contain a white dwarf and a Mira-type variable in a binary system. The orbital period is approximately 44 years.[6] The main Mira-type star is a red giant, and varies in brightness by a factor of several hundred and with a period of slightly more than a year; this variability was discovered by Karl Ludwig Harding in 1810. It has a distance of about 200 parsec, and is one of the nearest symbiotic stars and a well known jet source.[9] The two components have been resolved at a separation of 55 mas.[10] By its gravitational pull, the white dwarf draws in material from the red giant and occasionally ejects some of the surplus in weird loops to form the nebula seen in the linked image.[11] The whole system appears reddened because it is situated in a very dusty region of space, and its blue light is absorbed before reaching Earth. The nebula around R Aquarii is also known as Cederblad 211.[12] It is possible that the nebula is the remnant of a nova-like outburst, which may have been observed by Japanese astronomers, in the year 930 AD.[13] It is reasonably bright but small and dominated by its central star. Visual observations are difficult and rare.[14] The central region of the jet shows an ejection that took place around 190 years ago, as well as much younger structures.[15] The giant primary star is a Mira variable, a star that pulsates and changes temperature, leading to very large visual brightness changes. The total range of 5.2 - 12.4 is a variation of 750 times in brightness, from a naked eye star to one beyond the range of binoculars. The pulsations occur every 390 days but are not entirely regular.[3] Gallery{{Gallery|align=center|File:R Aquarii peculiar stellar relationship captured by SPHERE.jpg |R Aquarii peculiar stellar relationship captured by SPHERE.[16] |File:VLT view of binary system R Aquarii from 2012.tif |R Aquarii as seen in 2012 by ESO's Very Large Telescope.[17] |File:Raquariis.jpg |R Aquarii and its surrounding nebulosity |File:Artists Impression of R Aquarii, A Symbiotic Star.jpg |Artists Impression of R Aquarii during an outburst |File:R Aquarii.jpg |The jet and central regions of the nebula around R Aquarii |File:Symbiotic System R Aquarii.png |HST image of R Aquarii }} References1. ^1 {{cite journal|bibcode=2007A&A...474..653V|title=Validation of the new Hipparcos reduction|journal=Astronomy and Astrophysics|volume=474|issue=2|pages=653|author1=Van Leeuwen|first1=F.|year=2007|doi=10.1051/0004-6361:20078357|arxiv = 0708.1752 }} 2. ^1 {{cite journal|bibcode=1982AJ.....87.1791C|title=Red variable stars. I - UBVRI photometry and photometric properties|journal=Astronomical Journal|volume=87|pages=1791|author1=Celis s.|first1=L.|year=1982|doi=10.1086/113268}} 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. ^{{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 {{cite journal|bibcode=2014PASJ...66...38M|title=Accurate parallax measurement toward the symbiotic star R Aquarii|journal=Publications of the Astronomical Society of Japan|volume=66|issue=2|pages=38|author1=Min|first1=Cheulhong|last2=Matsumoto|first2=Naoko|last3=Kim|first3=Mi Kyoung|last4=Hirota|first4=Tomoya|last5=Shibata|first5=Katsunori M.|last6=Cho|first6=Se-Hyung|last7=Shizugami|first7=Makoto|last8=Honma|first8=Mareki|year=2014|doi=10.1093/pasj/psu003|arxiv = 1401.5574 }} 6. ^1 2 3 4 {{cite journal | title=The spectroscopic orbit and the geometry of R Aquarii | author=M. Gromadzki | author2=J. Mikołajewska | last-author-amp=yes | journal=Astronomy & Astrophysics | date=March 2009 | volume=495 | issue=3 | pages=931–936 | bibcode=2009A&A...495..931G | doi=10.1051/0004-6361:200810052 | arxiv = 0804.4139}} 7. ^1 2 {{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}} 8. ^{{Cite web|url=https://www.aavso.org/vsots_raqr|title=R Aquarii {{!}} aavso.org|website=www.aavso.org|language=en|access-date=2018-07-11}} 9. ^{{cite web|author=Stute, Matthias|author2=Sahai, Raghvendra|title=Hydrodynamical Simulations of the Jet in the Symbiotic Star MWC 560|url=http://hdl.handle.net/2014/41009|work=The Astrophysical Journal|publisher=The American Astronomical Society|accessdate=10 October 2011}} 10. ^{{cite journal|bibcode=1997ApJ...482L..85H|title=Spatial Resolution of the R Aquarii Binary System|journal=The Astrophysical Journal|volume=482|pages=L85|author1=Hollis|first1=J. M.|last2=Pedelty|first2=J. A.|last3=Lyon|first3=R. G.|year=1997|doi=10.1086/310687}} 11. ^{{cite web | url = http://aladin.u-strasbg.fr/AladinPreview?-c=23+43+49.4616-15+17+04.202&ident=V*+R+Aqr&submit=Aladin+previewer | title = Aladin previewer | publisher = CDS}} 12. ^{{cite journal|bibcode=1946MeLuS.119....1C|title=Studies of bright diffuse galactic nebulae with special regard to their spatial distribution|journal=Lund Medd. Astron. Obs. Ser. II|volume=119|pages=1|author1=Cederblad|first1=S|year=1946}} 13. ^{{cite journal|doi=10.1038/298540a0|title=The peculiar variable star R Aquarii and its jet|journal=Nature|volume=298|issue=5874|pages=540|year=1982|last1=Kafatos|first1=Minas|last2=Michalitsianos|first2=Andrew G|bibcode=1982Natur.298..540K}} 14. ^{{cite web|url=http://www.skyandtelescope.com/observing/celestial-objects-to-watch/variable-stars/the-drama-ridden-couple-of-r-aquarii/|title=The Drama-Ridden Couple of R Aquarii|publisher=Sky & Telescope|accessdate=2018-01-18}} 15. ^{{cite journal|bibcode=1994A&A...287..154P|title=New HST observations of the core of R Aquarii. 1: Imaging|journal=Astronomy and Astrophysics|volume=287|pages=154|author1=Paresce|first1=Francesco|last2=Hack|first2=Warren|year=1994}} 16. ^{{cite web |title=Dancing with the Enemy - ESO’s R Aquarii Week continues with the sharpest R Aquarii image ever |url=https://www.eso.org/public/news/eso1840/ |website=www.eso.org |accessdate=12 December 2018 |language=en}} 17. ^{{cite web |title=VLT view of binary system R Aquarii from 2012 |url=https://www.eso.org/public/images/potw1850a/ |website=www.eso.org |accessdate=10 December 2018 |language=en}} External links
10 : Aquarius (constellation)|M-type giants|Mira variables|Spectroscopic binaries|Henry Draper Catalogue objects|Objects with variable star designations|HR objects|Hipparcos objects|Durchmusterung objects|Z Andromedae variables |
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