View source for Sextans Dwarf Spheroidal

{{Short description|Galaxy in the constellation Sextans}}
{{Infobox Galaxy
| name = Sextans Dwarf Spheroidal
| image = Enana-Sextans-B-Ugc-5373.jpg
| epoch = [[Epoch (astronomy)#Julian years and J2000|J2000]]
| type = dSph<ref name="ned">{{cite web
  | title=NASA/IPAC Extragalactic Database
  | work=Results for Sextans Dwarf
  | url=http://nedwww.ipac.caltech.edu/
  | accessdate=2006-11-29 }}</ref>
| ra = {{RA|10|13|02.9}}<ref name="ned" />
| dec = {{DEC|-01|36|53}}<ref name="ned" />
| dist_ly = [[1 E18 m|290 ± 30]] [[light-year|kly]] (90 ± 10 [[parsec|kpc]])<ref name="karachentsevetal2004">{{cite journal
  | author=I. D. Karachentsev| author2=V. E. Karachentseva| author3=W. K. Hutchmeier| author4=D. I. Makarov
  | title=A Catalog of Neighboring Galaxies
  | journal=Astronomical Journal
  | date=2004
  | volume=127
  | issue=4
  | pages=2031–2068
  | bibcode=2004AJ....127.2031K
  | doi=10.1086/382905| doi-access=free
  }}</ref><ref name="Karachentsevetal2006">{{cite journal
  | author=Karachentsev, I. D.| author2=Kashibadze, O. G.
  | title=Masses of the local group and of the M81 group estimated from distortions in the local velocity field
  | journal=Astrophysics
  | date=2006
  | volume=49
  | issue=1
  | pages=3–18
  | bibcode=2006Ap.....49....3K
  | doi=10.1007/s10511-006-0002-6 | s2cid=120973010
 }}</ref>
| z = 224 ± 2 km/[[second|s]]<ref name="ned" />
| appmag_v = 10.4<ref name="ned" />
| size_v = 30.0{{prime}} × 12.0{{prime}}<ref name="ned" />
| constellation name = [[Sextans]]
| notes = satellite galaxy of the [[Milky Way]]
| names = Sextans I,<ref name="ned" /> LEDA 88608<ref name="ned" />
}}

The '''Sextans Dwarf Spheroidal''' is a [[dwarf spheroidal galaxy]] that was discovered in 1990 by [[Mike Irwin]] as the 8th satellite of the [[Milky Way]],<ref>{{cite journal|author=M. J. Irwin|author2=P. S. Bunclark|author3=M. T. Bridgeland|author4=R. G. McMahon|title=A new satellite galaxy of the Milky Way in the constellation of Sextans|journal=[[Monthly Notices of the Royal Astronomical Society]]|date=1990|volume=244|pages=16–19|bibcode=1990MNRAS.244P..16I}}</ref> located in the [[constellation]] of [[Sextans]].  It is also an [[elliptical galaxy]], and displays a [[redshift]] because it is receding from the Sun at 224&nbsp;km/s (72&nbsp;km/s from the Galaxy). The distance to the galaxy is 320,000 light-years and the diameter is 8,400 light-years along its major axis.<ref>{{cite web | author = Hartmut Frommert | title = Sextans Dwarf  | url = http://spider.seds.org/spider/LG/sex_dw.html  | publisher = SEDS | accessdate = 2015-03-21}}</ref>

Like other dwarf spheroidal galaxies, the Sextans Dwarf's population consists of old, [[metallicity|metal-poor]] stars: one study found that the majority of stars have a metallicity between [Fe/H] = −3.2 and −1.4. An analysis of several stars found them to also be deficient in [[barium]], except for one star.<ref>{{cite journal|doi=10.1093/mnras/stab3189|arxiv=2110.09402|title=The formation of the Milky Way halo and its dwarf satellites: A NLTE–1D abundance analysis. V. The Sextans galaxy|year=2022|last1=Mashonkina|first1=L.|last2=Pakhomov|first2=Yu V.|last3=Sitnova|first3=T.|last4=Jablonka|first4=P.|last5=Yakovleva|first5=S. A.|last6=Belyaev|first6=A. K.|journal=Monthly Notices of the Royal Astronomical Society|volume=509|issue=3|pages=3626–3642|doi-access=free }}</ref>

==References==
{{reflist}}

{{Sky|10|13|02.9|-|01|36|53|290000}}
{{Milky Way}}
{{Sextans}}

{{DEFAULTSORT:Galaxy, Sextans Dwarf Spheroidal}}
[[Category:Dwarf spheroidal galaxies]]
[[Category:Local Group]]
[[Category:Milky Way Subgroup]]
[[Category:Sextans]]
[[Category:Astronomical objects discovered in 1990|?]]