Beta Gruis

Quality 0.50 · 0 views · Updated 2 months ago

Star in the constellation of Grus

title: "Beta Gruis" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["m-type-giants", "semiregular-variable-stars", "asymptotic-giant-branch-stars", "grus-(constellation)", "bayer-objects", "durchmusterung-objects", "henry-draper-catalogue-objects", "hipparcos-objects", "bright-star-catalogue-objects", "stars-with-proper-names", "gould-objects"] description: "Star in the constellation of Grus" topic_path: "science/astronomy" source: "https://en.wikipedia.org/wiki/Beta_Gruis" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Star in the constellation of Grus ::

| name=Beta Gruis | image= |image=Grus constellation map.svg|alt=|float=center|width=240 |label=|position=right |mark=Red circle.svg|mark_width=14|mark_link=Beta Gruis|x=413|y=712 |caption=Location of β Gruis (circled) | epoch = J2000 | ra = | dec = | appmag_v = 2.146 (2.0 - 2.3) | constell = Grus | type = AGB | class = M4.5 III | b-v = +1.620 | u-b = +1.757 | variable = SRb | radial_v = +1.6 | prop_mo_ra = +135.16 | prop_mo_dec = −4.38 | parallax = 18.43 | p_error = 0.42 | parallax_footnote = | absmag_v = | mass = 2.4 | radius = 154 | luminosity = | temperature = | gravity = 0.4 | metal_fe = 0.0 | rotational_velocity = | age_myr = 450 | names = Tiaki, Beta Gru, CD−47 14308, FK5 856, HR 8636, HD 214952, HIP 112122, SAO 231258. | Simbad = HD+214952

Beta Gruis (β Gruis, abbreviated Beta Gru, β Gru), formally named Tiaki , is the second brightest star in the southern constellation of Grus. It was once considered the rear star in the tail of the constellation of the (Southern) Fish, Piscis Austrinus: it, with Alpha, Delta, Theta, Iota, and Lambda Gruis, belonged to Piscis Austrinus in medieval Arabic astronomy.

Nomenclature

β Gruis (Latinised to Beta Gruis) is the star's Bayer designation.

It bore the traditional Tuamotuan name of Tiaki. In 2016, the IAU organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN approved the name Tiaki for this star on 5 September 2017 and it is now so included in the List of IAU-approved Star Names.

In Chinese, 鶴 (Hè), meaning Crane, refers to an asterism consisting of Beta Gruis, Alpha Gruis, Epsilon Gruis, Eta Gruis, Delta Tucanae, Zeta Gruis, Iota Gruis, Theta Gruis, Delta² Gruis and Mu¹ Gruis. Consequently, Beta Gruis itself is known as 鶴二 (Hè èr, ). The Chinese name gave rise to another English name, Ke.

Properties

::figure[src="https://upload.wikimedia.org/wikipedia/commons/5/55/BetaGruLightCurve.png" caption="visual band]] [[light curve]] for Beta Gruis, plotted from data published by Otero and Moon (2006). The inset plot shows the points plotted in red with an expanded scale."] ::

Beta Gruis is a red giant star on the asymptotic giant branch with an estimated mass of about 2.4 times that of the Sun and a surface temperature of approximately 3,500 K, just over half the surface temperature of the Sun. This low temperature accounts for the dull red color of an M-type star. The total luminosity is about 3,200 times that of the Sun, and it has 150 times the Sun's radius.

It is one of the brightest stars at infrared and near-infrared wavelenghts. At the K band, it is the fifth-brightest star in the night sky.

Alan William James Cousins announced that Beta Gruis is a variable star in 1952. Beta Gruis is a semiregular variable (SRb) star that varies in magnitude by about 0.4. It varies between intervals when it displays regular changes with a 37-day periodicity and times when it undergoes slow irregular variability.

References

References

  1. "Naming Stars". IAU.org.
  2. "WG Triennial Report (2015-2018) - Star Names".
  3. "IAU Working Group on Star Names (WGSN)".
  4. {{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.
  5. {{in lang. zh [http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/c_research_chinengstars_ala_alz.htm 香港太空館 - 研究資源 - 亮星中英對照表] {{webarchive. link. (2008-10-25 , Hong Kong Space Museum. Accessed on line November 23, 2010.)
  6. [https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Grus*.html Richard Hinckley Allen: Star Names — Their Lore and Meaning: Grus]
  7. "Kmag < -3.22".
  8. (April 1952). "Bright variable stars in southern hemisphere (second list)". The Observatory.
  9. van Leeuwen, F.. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics.
  10. Kaler, Jim. "Beta Gruis".
  11. (2017-10-01). "Fundamental parameters and infrared excesses of Tycho-Gaia stars". Monthly Notices of the Royal Astronomical Society.
  12. (December 1999). "Evolution of X-ray activity and rotation on G-K giants". Astronomy and Astrophysics.
  13. (1978). "Michigan catalogue of two-dimensional spectral types for the HD stars". Dept. of Astronomy, University of Michigan.
  14. (1999). "Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions". Astronomisches Rechen-Institut Heidelberg.
  15. (1966). "A System of photometric standards". Publicaciones Universidad de Chile, Department de Astronomy.
  16. (1963). "[[Star Names: Their Lore and Meaning]]". [[Dover Publications]] Inc..
  17. (December 2006). "The Characteristic Period of Pulsation of β Gruis". The Journal of the American Association of Variable Star Observers.
  18. (November 1986). "Constraints on the Outer Atmospheric Structure of Late Type Giant Stars with IUE Application to Alpha-Tauri K5III and Beta-Gruis M5III". [[Monthly Notices of the Royal Astronomical Society]].
  19. (October 2006). "Spectral Irradiance Calibration in the Infrared. XVI. Improved Accuracy in the Infrared Spectra of the Secondary and Tertiary Standard Calibration Stars". The Astronomical Journal.
  20. "V* bet Gru -- Variable Star". [[Centre de Données astronomiques de Strasbourg]].
  21. (2023-12-01). "Extended far-UV emission surrounding asymptotic giant branch stars as seen by GALEX". Astronomy & Astrophysics.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::

m-type-giantssemiregular-variable-starsasymptotic-giant-branch-starsgrus-(constellation)bayer-objectsdurchmusterung-objectshenry-draper-catalogue-objectshipparcos-objectsbright-star-catalogue-objectsstars-with-proper-namesgould-objects