Lambda Aquarii: Difference between revisions

Lambda Aquarii
	Location of λ Aquarii (circled)
Observation data; Epoch J2000 Equinox J2000
Constellation	Aquarius
Right ascension	22h 52m 36.87723s
Declination	−07° 34′ 46.5830″
Apparent magnitude (V)	3.722 (3.57 to 3.80)
Characteristics
Spectral type	M2.5 IIIa Fe–1
U−B color index	+1.721
B−V color index	+1.641
Variable type	Lb
Astrometry
Radial velocity (Rv)	−10.46±0.53 km/s
Proper motion (μ)	RA: +11.806 mas/yr ; Dec.: +34.967 mas/yr
Parallax (π)	10.6766 ± 0.5672 mas
Distance	310 ± 20 ly ; (94 ± 5 pc)
Absolute magnitude (MV)	–1.5
Details
Mass	3.6 M☉
Radius	44.10+21.14; −13.20 R☉
Luminosity	698.5±41.5 L☉
Temperature	3,835 K
Metallicity [Fe/H]	–2.25 dex
Other designations
	λ Aqr, 73 Aquarii, BD–08°968, FK5 864, HD 216386, HIP 112961, HR 8698, SAO 146362
Database references
SIMBAD	data

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Lambda Aquarii, informally known as Hydor (/ˈhaɪdɔːr/),^[9]^[10] is a variable star in the equatorial constellation of Aquarius. The name is Latinized from the Bayer designation λ Aquarii. The apparent visual magnitude of this star ranges around 3.722,^[2] which is bright enough to be visible with the naked eye. The star is eclipsed by the sun from about 1-4 March;^[11] thus the star can be viewed the whole night, crossing the sky, in early September, in the current epoch. It lies 0.39 degrees south of the ecliptic.^[12] It is located at a distance of approximately 310 light-years (95 pc) from the Sun based on parallax,^[1] but is drifting closer with a radial velocity of −10.5 km/s.^[5]

The stellar classification of Lambda Aquarii is M2.5 IIIa Fe–1,^[4] indicating this is an aging red giant star with an underabundance of iron showing in its spectrum. This star is on the asymptotic giant branch and is generating energy through the nuclear fusion of hydrogen and helium along concentric shells surrounding an inert core of carbon and oxygen.^[13] It is classified as slow irregular variable and pulsation periods of 24.5, 32.0, and 49.5 days have been identified.^[14]

Naming

Hydor is from Greek Ὕδωρ "water", a name given by Proclus, according to Richard Hinckley Allen. Another Greek name for the star is Ekkhysis, from εκχυσις "outpouring".^[10]

In Chinese, 壘壁陣 (Lěi Bì Zhèn), meaning Line of Ramparts, refers to an asterism consisting of λ Aquarii, κ Capricorni, ε Capricorni, γ Capricorni, δ Capricorni, ι Aquarii, σ Aquarii, φ Aquarii, 27 Piscium, 29 Piscium, 33 Piscium and 30 Piscium.^[15] Consequently, λ Aquarii itself is 壘壁陣七 (Lěi Bì Zhèn qī, English: the Seventh Star of Line of Ramparts.)^[16]

References

^ ^a ^b ^c ^d ^e ^f ^g ^h Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
^ ^a ^b ^c ^d Gutierrez-Moreno, Adelina; et al. (1966), "A System of photometric standards", Publ. Dept. Astron. Univ. Chile, 1, Publicaciones Universidad de Chile, Department de Astronomy: 1–17, Bibcode:1966PDAUC...1....1G.
^ ^a ^b Samus, N. N.; Kazarovets, E. V.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 61 (1) (5.1 ed.): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869. Retrieved 2019-11-23.
^ ^a ^b Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
^ ^a ^b Famaey, B.; et al. (May 2009), "Spectroscopic binaries among Hipparcos M giants. I. Data, orbits, and intrinsic variations", Astronomy and Astrophysics, 498 (2): 627–640, arXiv:0901.0934, Bibcode:2009A&A...498..627F, doi:10.1051/0004-6361/200810698, S2CID 18739721.
^ ^a ^b Dupree, A. K.; Li, Timothy Q.; Smith, Graeme H. (October 2007), "Hubble Space Telescope Observations of Chromospheres in Metal-Deficient Field Giants", The Astronomical Journal, 134 (4): 1348–1359, arXiv:0709.1709, Bibcode:2007AJ....134.1348D, doi:10.1086/520925, S2CID 14481140.
^ ^a ^b Tsuji, Takashi (May 2007). "Isotopic abundances of Carbon and Oxygen in Oxygen-rich giant stars". In Kupka, F.; Roxburgh, I.; Chan, K. (eds.). Convection in Astrophysics, Proceedings of IAU Symposium #239 held 21-25 August, 2006 in Prague, Czech Republic. Proceedings of the International Astronomical Union. Vol. 2. pp. 307–310. arXiv:astro-ph/0610180. Bibcode:2007IAUS..239..307T. doi:10.1017/S1743921307000622.
^ "* lam Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-07-01.
^ Kaler, Jim. "Hydor". Retrieved 2017-08-17.
^ ^a ^b Allen, Richard Hinckey. "Star Names: Their Lore and Meaning". Retrieved 2017-08-17.
^ In the Sky Earth astronomy reference utility showing the ecliptic and relevant date as at J2000 - present
^ John Pratt's stars re-publication by Dr J.P. Pratt (Doctor of Astronomy, University of Arizona) of sidereal coordinate data. Note: possibly a non-book published source.
^ Lebzelter, T.; Hron, J. (January 2008), "BRITE stars on the AGB" (PDF), Communications in Asteroseismology, 152: 178–181, Bibcode:2008CoAst.152..178L, doi:10.1553/cia152s178.
^ Tabur, V.; et al. (December 2009), "Long-term photometry and periods for 261 nearby pulsating M giants", Monthly Notices of the Royal Astronomical Society, 400 (4): 1945–1961, arXiv:0908.3228, Bibcode:2009MNRAS.400.1945T, doi:10.1111/j.1365-2966.2009.15588.x, S2CID 15358380.
^ (in Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 7 日

External links

[GaiaDR2-1] ^ ^a ^b ^c ^d ^e ^f ^g ^h Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.

[sps1966-2] Gutierrez-Moreno, Adelina; et al. (1966), "A System of photometric standards", Publ. Dept. Astron. Univ. Chile, 1, Publicaciones Universidad de Chile, Department de Astronomy: 1–17, Bibcode:1966PDAUC...1....1G.

[Samus2017-3] Samus, N. N.; Kazarovets, E. V.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 61 (1) (5.1 ed.): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869. Retrieved 2019-11-23.

[mnras389_2_869-4] Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.

[aaa498_2_627-5] Famaey, B.; et al. (May 2009), "Spectroscopic binaries among Hipparcos M giants. I. Data, orbits, and intrinsic variations", Astronomy and Astrophysics, 498 (2): 627–640, arXiv:0901.0934, Bibcode:2009A&A...498..627F, doi:10.1051/0004-6361/200810698, S2CID 18739721.

[aj134_4_1348-6] Dupree, A. K.; Li, Timothy Q.; Smith, Graeme H. (October 2007), "Hubble Space Telescope Observations of Chromospheres in Metal-Deficient Field Giants", The Astronomical Journal, 134 (4): 1348–1359, arXiv:0709.1709, Bibcode:2007AJ....134.1348D, doi:10.1086/520925, S2CID 14481140.

[tsuji2007-7] Tsuji, Takashi (May 2007). "Isotopic abundances of Carbon and Oxygen in Oxygen-rich giant stars". In Kupka, F.; Roxburgh, I.; Chan, K. (eds.). Convection in Astrophysics, Proceedings of IAU Symposium #239 held 21-25 August, 2006 in Prague, Czech Republic. Proceedings of the International Astronomical Union. Vol. 2. pp. 307–310. arXiv:astro-ph/0610180. Bibcode:2007IAUS..239..307T. doi:10.1017/S1743921307000622.

[SIMBAD-8] "* lam Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-07-01.

[Kaler-9] Kaler, Jim. "Hydor". Retrieved 2017-08-17.

[Allen-10] Allen, Richard Hinckey. "Star Names: Their Lore and Meaning". Retrieved 2017-08-17.

[in-the-sky-11] In the Sky Earth astronomy reference utility showing the ecliptic and relevant date as at J2000 - present

[Pratt-12] John Pratt's stars re-publication by Dr J.P. Pratt (Doctor of Astronomy, University of Arizona) of sidereal coordinate data. Note: possibly a non-book published source.

[cia152_178-13] Lebzelter, T.; Hron, J. (January 2008), "BRITE stars on the AGB" (PDF), Communications in Asteroseismology, 152: 178–181, Bibcode:2008CoAst.152..178L, doi:10.1553/cia152s178.

[mnras400_4_1945-14] Tabur, V.; et al. (December 2009), "Long-term photometry and periods for 261 nearby pulsating M giants", Monthly Notices of the Royal Astronomical Society, 400 (4): 1945–1961, arXiv:0908.3228, Bibcode:2009MNRAS.400.1945T, doi:10.1111/j.1365-2966.2009.15588.x, S2CID 15358380.

[15] (in Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.

[16] (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 7 日

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@@ Line 1: / Line 1: @@
 {{short description|Star in the constellation Aquarius}}
-{{Starbox begin
+{{Starbox begin}}
- | name=λ Aquarii
-}}
 {{Starbox image
  | image=
@@ Line 11: / Line 9: @@
 |x=341|y=437
 }}
-|caption=Location of λ Aquarii (circled)
+ | caption=Location of λ Aquarii (circled)
 }}
 {{Starbox observe
  | epoch       = J2000
- | ra          = {{RA|22|52|36.87441}}<ref name=aaa474_2_653/>
+ | ra          = {{RA|22|52|36.87723}}<ref name=GaiaDR2/>
- | dec         = {{DEC|−07|34|46.5542}}<ref name=aaa474_2_653/>
+ | dec         = {{DEC|−07|34|46.5830}}<ref name=GaiaDR2/>
- | appmag_v    = 3.722<ref name=sps1966/>
+ | appmag_v    = 3.722<ref name=sps1966/> {{nowrap|(3.57 to 3.80)}}<ref name=Samus2017/>
  | constell    = [[Aquarius (constellation)|Aquarius]]
 }}
@@ Line 24: / Line 22: @@
  | b-v         = +1.641<ref name=sps1966/>
  | u-b         = +1.721<ref name=sps1966/>
+ | variable    = [[Slow irregular variable|Lb]]<ref name=Samus2017/>
- | variable    = [[Slow irregular variable|Lb]]<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|display-authors=etal|last1=Samus|first1=N. N.|last2=Durlevich|first2=O. V.|year=2009}}</ref>
 }}
 {{Starbox astrometry
- | radial_v    = {{nowrap|−10.46 ± 0.53}}<ref name=aaa498_2_627/>
+ | radial_v    = {{val|−10.46|0.53}}<ref name=aaa498_2_627/>
- | prop_mo_ra  = +17.02<ref name=aaa474_2_653/>
+ | prop_mo_ra  = +11.806<ref name=GaiaDR2/>
- | prop_mo_dec = +33.03<ref name=aaa474_2_653/>
+ | prop_mo_dec = +34.967<ref name=GaiaDR2/>
- | parallax    = 8.47
+ | parallax    = 10.6766
- | p_error     = 0.66
+ | p_error     = 0.5672
- | parallax_footnote = <ref name=aaa474_2_653/>
+ | parallax_footnote = <ref name=GaiaDR2/>
  | absmag_v    = –1.5<ref name=aj134_4_1348/>
 }}
 {{Starbox detail
  | mass        = 3.6<ref name=tsuji2007/>
- | radius      =
+ | radius      = {{val|44.10|21.14|13.20}}<ref name=GaiaDR2/>
- | luminosity  =
+ | luminosity  = {{val|698.5|41.5}}<ref name=GaiaDR2/>
  | temperature = 3,835<ref name=tsuji2007/>
  | metal_fe    = –2.25<ref name=aj134_4_1348/>
@@ Line 45: / Line 43: @@
 }}
 {{Starbox catalog
- | names=[[Flamsteed designation|73]]&nbsp;Aquarii, [[Bonner Durchmusterung|BD]]–08°968, [[FK5]]&nbsp;864, [[Henry Draper Catalogue|HD]]&nbsp;216386, [[Hipparcos catalogue|HIP]]&nbsp;112961, [[Bright Star Catalogue|HR]]&nbsp;8698, [[Smithsonian Astrophysical Observatory Star Catalog|SAO]]&nbsp;146362.<ref name=SIMBAD/>
+ | names = {{odlist | B=λ Aqr | F=73&nbsp;Aquarii | BD=–08°968 | FK5=864 | HD=216386 | HIP=112961 | HR=8698 | SAO=146362 }}<ref name=SIMBAD/>
 }}
 {{Starbox reference
@@ Line 52: / Line 50: @@
 {{Starbox end}}
+'''Lambda Aquarii''', informally known as '''Hydor''' ({{IPAc-en|'|h|ai|d|ɔr}}),<ref name=Kaler/><ref name=Allen/> is a [[variable star]] in the [[celestial equator|equatorial]] [[constellation]] of [[Aquarius (constellation)|Aquarius]]. The name is [[Romanization of Greek|Latinized]] from the [[Bayer designation]] λ Aquarii. The [[apparent visual magnitude]] of this star ranges around 3.722,<ref name=sps1966/> which is bright enough to be visible with the naked eye. The star is eclipsed by the sun from about 1-4 March;<ref name=in-the-sky/> thus the star can be viewed the whole night, crossing the sky, in early September, in the current epoch.  It lies 0.39 degrees south of the ecliptic.<ref name=Pratt/> It is located at a distance of approximately {{convert|310|ly|pc|lk=on}} from the [[Sun]] based on [[stellar parallax|parallax]],<ref name=GaiaDR2/> but is drifting closer with a [[radial velocity]] of −10.5&nbsp;km/s.<ref name=aaa498_2_627/>
-'''Lambda Aquarii''' (λ Aqr, λ Aquarii), informally known as '''Hydor''' {{IPAc-en|'|h|ai|d|ɔr}},<ref name=Kaler>{{cite web
-  |title=Hydor
-  |first=Jim|last=Kaler
-  |author-link=Jim Kaler
-  |url=http://stars.astro.illinois.edu/sow/hydor.html
-  |access-date=2017-08-17}}</ref><ref name=Allen/> is the [[Bayer designation]] for a [[star]] in the [[celestial equator|equatorial]] [[constellation]] of [[Aquarius (constellation)|Aquarius]]. The [[apparent visual magnitude]] of this star is 3.722,<ref name=sps1966/> which is bright enough to be visible with the naked eye. It is roughly {{convert|390|ly|pc|lk=on}} from [[Earth]].<ref name=aaa474_2_653/>
+The [[stellar classification]] of Lambda Aquarii is {{nowrap|M2.5 IIIa Fe–1}},<ref name=mnras389_2_869/> indicating this is an aging [[red giant]] star with an underabundance of iron showing in its [[stellar spectrum|spectrum]]. This star is on the [[asymptotic giant branch]] and is generating energy through the nuclear fusion of hydrogen and helium along concentric shells surrounding an inert core of carbon and oxygen.<ref name=cia152_178/> It is classified as [[slow irregular variable]] and pulsation periods of 24.5, 32.0, and 49.5 days have been identified.<ref name=mnras400_4_1945/>
-==Properties==
-Lambda Aquarii is a [[red giant]] star with a [[stellar classification]] of M2.5&nbsp;III.<ref name=mnras389_2_869/> It is classified as [[slow irregular variable]] and pulsation periods of 24.5, 32.0, and 49.5 days have been identified.<ref name=mnras400_4_1945/> This star is on the [[asymptotic giant branch]] and is generating energy through the nuclear fusion of hydrogen and helium along concentric shells surrounding an inert core of carbon and oxygen.<ref name=cia152_178/>
 ==Naming==
-''Hydor'' is from Greek Ὕδωρ "water", a name given by [[Proclus]], according to [[Richard Hinckley Allen]]. Another Greek name for the star is ''Ekkhysis'', from εκχυσις "outpouring".<ref name=Allen>{{cite web
+''Hydor'' is from Greek Ὕδωρ "water", a name given by [[Proclus]], according to [[Richard Hinckley Allen]]. Another Greek name for the star is ''Ekkhysis'', from εκχυσις "outpouring".<ref name=Allen/>
-  |title=Star Names: Their Lore and Meaning
-  |first=Richard Hinckey|last=Allen
-  |author-link=Richard Hinckley Allen
-  |url=https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Aquarius*.html
-  |access-date=2017-08-17}}</ref>
 In [[Chinese astronomy|Chinese]], {{lang|zh|壘壁陣}} ({{lang|zh-Latn|Lěi Bì Zhèn}}), meaning ''[[Encampment (Chinese constellation)|Line of Ramparts]]'', refers to an asterism consisting of λ Aquarii, [[Kappa Capricorni|κ Capricorni]], [[Epsilon Capricorni|ε Capricorni]], [[Gamma Capricorni|γ Capricorni]], [[Delta Capricorni|δ Capricorni]], [[Iota Aquarii|ι Aquarii]], [[Sigma Aquarii|σ Aquarii]], [[Phi Aquarii|φ Aquarii]], [[27 Piscium]], [[29 Piscium]], [[33 Piscium]] and [[30 Piscium]].<ref>{{in lang|zh}} ''中國星座神話'', written by 陳久金. Published by 台灣書房出版有限公司, 2005, {{ISBN|978-986-7332-25-7}}.</ref> Consequently, λ Aquarii itself is {{lang|zh|壘壁陣七}} ({{lang|zh-Latn|Lěi Bì Zhèn qī}}, {{lang-en|the Seventh Star of Line of Ramparts}}.)<ref>{{in lang|zh}} [http://aeea.nmns.edu.tw/2006/0607/ap060707.html AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 7 日]</ref>
-==Night viewing==
-The star is eclipsed by the sun from about 1-4 March.<ref>[http://in-the-sky.org/skymap.php?year=2019&month=3&day=2 In the Sky] Earth astronomy reference utility showing the ecliptic and relevant date as at J2000 - present</ref> Thus the star can be viewed the whole night, crossing the sky, in early September, in the current epoch.  It lies 0.39 degrees south of the ecliptic.<ref>[http://www.johnpratt.com/items/astronomy/zodiac/zodiac_stars.html John Pratt's stars] re-publication by Dr J.P. Pratt (Doctor of Astronomy, University of Arizona) of sidereal coordinate data. Note: possibly a non-book published source.</ref>
 ==References==
 {{reflist|refs=
+<ref name=GaiaDR2>{{Cite Gaia DR2|2610370969482732672}}</ref>
-<ref name=aaa474_2_653>{{citation | first=F. | last=van Leeuwen |date=November 2007 | title=Validation of the new Hipparcos reduction | journal=Astronomy and Astrophysics | volume=474 | issue=2 | pages=653–664 | bibcode=2007A&A...474..653V | doi=10.1051/0004-6361:20078357 | postscript=. |arxiv = 0708.1752 | s2cid=18759600 }}</ref>
+<ref name=Kaler>{{cite web
+  |title=Hydor
+  |first=Jim|last=Kaler
+  |author-link=Jim Kaler
+  |url=http://stars.astro.illinois.edu/sow/hydor.html
+  |access-date=2017-08-17}}</ref>
+<ref name=Samus2017>{{Cite journal
+ | display-authors=2 | last1=Samus | first1=N. N.
+ | last2=Kazarovets | first2=E. V. | last3=Durlevich| first3=Olga V.
+ | last4=Kireeva | first4=N. N. | last5=Pastukhova | first5=E.N.
+ | title=General Catalogue of Variable Stars
+ | journal=Astronomy Reports | edition=5.1
+ | year=2017 | pages=80–88 | volume=61 | issue=1
+ | url=http://www.sai.msu.su/gcvs/gcvs/ | access-date=2019-11-23
+ | bibcode=2017ARep...61...80S | s2cid=125853869
+ | doi=10.1134/S1063772917010085 }}</ref>
 <ref name=tsuji2007>{{cite conference | last1=Tsuji | first1=Takashi | contribution=Isotopic abundances of Carbon and Oxygen in Oxygen-rich giant stars | title=Convection in Astrophysics, Proceedings of IAU Symposium #239 held 21-25 August, 2006 in Prague, Czech Republic | journal=Proceedings of the International Astronomical Union | volume=2 | editor1-first=F. | editor1-last=Kupka | editor2-first=I. | editor2-last=Roxburgh | editor3-first=K. | editor3-last=Chan | pages=307–310 |date=May 2007 | doi=10.1017/S1743921307000622 | bibcode=2007IAUS..239..307T | arxiv=astro-ph/0610180 }}</ref>
@@ Line 97: / Line 98: @@
 <ref name=aj134_4_1348>{{citation | last1=Dupree | first1=A. K. | last2=Li | first2=Timothy Q. | last3=Smith | first3=Graeme H. | title=Hubble Space Telescope Observations of Chromospheres in Metal-Deficient Field Giants | journal=The Astronomical Journal | volume=134 | issue=4 | pages=1348–1359 |date=October 2007 | doi=10.1086/520925 | bibcode=2007AJ....134.1348D | postscript=. |arxiv = 0709.1709 | s2cid=14481140 }}</ref>
+<ref name=Pratt>[http://www.johnpratt.com/items/astronomy/zodiac/zodiac_stars.html John Pratt's stars] re-publication by Dr J.P. Pratt (Doctor of Astronomy, University of Arizona) of sidereal coordinate data. Note: possibly a non-book published source.</ref>
+<ref name=in-the-sky>[http://in-the-sky.org/skymap.php?year=2019&month=3&day=2 In the Sky] Earth astronomy reference utility showing the ecliptic and relevant date as at J2000 - present</ref>
+<ref name=Allen>{{cite web
+  |title=Star Names: Their Lore and Meaning
+  |first=Richard Hinckey|last=Allen
+  |author-link=Richard Hinckley Allen
+  |url=https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Aquarius*.html
+  |access-date=2017-08-17}}</ref>
 }}
@@ Line 107: / Line 119: @@
 {{DEFAULTSORT:Lambda Aquarii}}
-[[Category:Stars with proper names|Hydor]]
-[[Category:Henry Draper Catalogue objects|216386]]
-[[Category:Bayer objects|Aquarii, Lambda]]
-[[Category:Aquarius (constellation)]]
-[[Category:Slow irregular variables]]
 [[Category:M-type giants]]
+[[Category:Slow irregular variables]]
+[[Category:Aquarius (constellation)]]
+[[Category:Bayer objects|Aquarii, Lambda]]
+[[Category:Durchmusterung objects|BD-08 0968]]
 [[Category:Flamsteed objects|Aquarii, 073]]
-[[Category:HR objects|8698]]
+[[Category:Henry Draper Catalogue objects|216386]]
 [[Category:Hipparcos objects|112961]]
-[[Category:Durchmusterung objects|BD-08 0968]]
+[[Category:HR objects|8698]]
+[[Category:Stars with proper names|Hydor]]

Observation data Epoch J2000 Equinox J2000
Location of λ Aquarii (circled)
Constellation	Aquarius
Right ascension	22^h 52^m 36.87723^s^[1]
Declination	−07° 34′ 46.5830″^[1]
Apparent magnitude (V)	3.722^[2] (3.57 to 3.80)^[3]
Characteristics
Spectral type	M2.5 IIIa Fe–1^[4]
U−B color index	+1.721^[2]
B−V color index	+1.641^[2]
Variable type	Lb^[3]
Astrometry

Radial velocity (R_v)	−10.46±0.53^[5] km/s
Proper motion (μ)	RA: +11.806^[1] mas/yr Dec.: +34.967^[1] mas/yr
Parallax (π)	10.6766 ± 0.5672 mas^[1]
Distance	310 ± 20 ly (94 ± 5 pc)
Absolute magnitude (M_V)	–1.5^[6]

Details

Mass	3.6^[7] `M`_☉
Radius	44.10+21.14 −13.20^[1] `R`_☉
Luminosity	698.5±41.5^[1] `L`_☉
Temperature	3,835^[7] K
Metallicity [Fe/H]	–2.25^[6] dex

Other designations
λ Aqr, 73 Aquarii, BD–08°968, FK5 864, HD 216386, HIP 112961, HR 8698, SAO 146362^[8]
Database references
SIMBAD	data