View source for NGC 5822

{{Short description|Open cluster in the constellation Lupus}}
{{Infobox open cluster
 | name      = {{PAGENAME}}
 | image     = NGC_5822.png
 | caption   = NGC 5822 (taken from Stellarium)
 | credit    = <!-- Per MOS:CREDITS, credits are discouraged -->
 | epoch     = [[J2000]]
 | constellation = [[Lupus (constellation)|Lupus]]
 | ra        = {{RA|15|4|21.(2)}}<ref name=Cantat-Gaudin_Anders_2020/>
 | dec       = {{DEC|-54|23|5(8)}}<ref name=Cantat-Gaudin_Anders_2020/>
 | dist_ly   = {{cvt|822.3|pc|ly|order=flip|lk=on}}<ref name=Cantat-Gaudin_Anders_2020/>
 | dist_pc   = 
 | appmag_v  = 6.5<ref name=Seligman/>
 | size_v    = <!-- Angular size of the cluster: {{val|#.##|ul=arcsecond}} -->
 | radius_ly = {{cvt|8.0|±|0.4|pc|ly|order=flip}}<ref name=Bonatto_Bica_2005/>
 | mass_msol = {{val|1.7|e=3|p=~}}<ref name=Sun_et_al_2019/>
 | age       = {{val|900|100}}&nbsp;Myr<ref name=Carraro_et_al_2011/>
 | notes     = <!-- Unusual features -->
 | names     = [[New General Catalogue|NGC]] 5822, [[Collinder catalogue|Cr]] 289, ESO 176-SC 009<ref name="ned" />
}}

'''NGC 5822''' is an [[open cluster]] of stars in the southern [[constellation]] of [[Lupus (constellation)|Lupus]].<ref name=SIMBAD/> It was discovered by English Astronomer [[John Herschel]] on July 3, 1836,<ref name=Seligman/> and lies close to another cluster, [[NGC 5823]], which suggests there may be a physical association.<ref name=Bruck_et_al_1968/><ref name=Dawson1978/>

NGC 5822 is an intermediate age cluster, estimated at around 900&nbsp;million years old, and it is located nearby<ref name=Sun_et_al_2019/> at a distance of 2,700&nbsp;[[light year]]s.<ref name=Cantat-Gaudin_Anders_2020/> The [[Trumpler class]] of this cluster is III 2m.<ref name=Dawson1978/> It is richly populated<ref name=Carraro_et_al_2011/> with half the cluster members lying within an angular radius of {{val|22.1|ul=arcminute}}.<ref name=Cantat-Gaudin_Anders_2020/> The cluster is considered low mass at ~1,700 times the [[mass of the Sun]].<ref name=Sun_et_al_2019/> It has a [[core radius]] of {{val|1.1|0.1|u=pc}} and a limiting radius of {{val|8.0|0.4|u=pc}}.<ref name=Bonatto_Bica_2005/>

Measuring the abundances of a set of [[F-type star]]s that are probable members demonstrates the cluster [[metallicity]] is very similar to the [[Sun]].<ref name=Carraro_et_al_2011/> It displays an extended [[main sequence turnoff]] on the [[Hertzsprung–Russell diagram]], most likely due to differences in stellar rotation.<ref name=Sun_et_al_2019/> Two [[barium star]]s have been identified in NGC 5822, making it only the second cluster shown to host these objects as of 2013.<ref name=Katime_Santrich_et_al_2013/>

==Gallery==
<gallery>
File:NGC 5822 map.png|Map showing the location of NGC 5822
</gallery>

==References==
{{Reflist|refs=

<ref name=Seligman>{{cite web
 | title=NGC Objects: NGC 5800 - 5849
 | first=Courtney | last=Seligman
 | work=Celestial Atlas
 | url=https://cseligman.com/text/atlas/ngc58.htm#5822
 | access-date=2021-12-29 }}</ref>

<ref name=Bonatto_Bica_2005>{{cite journal
 | title=Detailed analysis of open clusters: A mass function break and evidence of a fundamental plane
 | last1=Bonatto | first1=C. | last2=Bica | first2=E.
 | journal=Astronomy and Astrophysics
 | volume=437 | issue=2 | date=July 2005 | pages=483–500
 | doi=10.1051/0004-6361:20042516 | arxiv=astro-ph/0503589
 | bibcode=2005A&A...437..483B | s2cid=18070831 }}</ref>

<ref name=Dawson1978>{{cite journal
 | title=DDO photometry of giants in four southern open clusters
 | last=Dawson | first=D. W.
 | journal=Astronomical Journal
 | volume=83 | pages=1424–1429 | date=November 1978
 | doi=10.1086/112334 | bibcode=1978AJ.....83.1424D }}</ref>

<ref name=Bruck_et_al_1968>{{cite journal
 | title=Three-colour photometry of southern galactic clusters IV: NGC 5822, 5823
 | display-authors=1 | last1=Bruck | first1=Mary T.
 | last2=Smyth | first2=Michael Jessop | last3=McLachlan | first3=A.
 | journal=Publications of the Royal Observatory, Edinburgh
 | volume=6 | number=9 | date=1968 | pages=209–223
 | bibcode=1968PROE....6..210B }}</ref>

<ref name=Katime_Santrich_et_al_2013>{{cite journal
 | title=Two Barium Stars in the Open Cluster NGC 5822
 | display-authors=1 | last1=Katime Santrich | first1=O. J.
 | last2=Pereira | first2=C. B. | last3=de Castro | first3=D. B.
 | journal=The Astronomical Journal
 | volume=146 | issue=2 | id=39 | pages=12 | date=August 2013
 | doi=10.1088/0004-6256/146/2/39 | bibcode=2013AJ....146...39K | doi-access=free }}</ref>

<ref name=Sun_et_al_2019>{{cite journal
 | title=Stellar Rotation and the Extended Main-sequence Turnoff in the Open Cluster NGC 5822
 | last1=Sun | first1=Weijia | last2=de Grijs | first2=Richard
 | last3=Deng | first3=Licai | last4=Albrow | first4=Michael D.
 | display-authors=1 | journal=The Astrophysical Journal
 | volume=876 | issue=2 | id=113 | pages=9
 | date=May 2019 | doi=10.3847/1538-4357/ab16e4
 | arxiv=1904.03547 | bibcode=2019ApJ...876..113S | s2cid=102350601 | doi-access=free }}</ref>

<ref name=Carraro_et_al_2011>{{cite journal
 | title=A UBVI and uvbyCaHβ Analysis of the Intermediate-age Open Cluster, NGC 5822
 | display-authors=1 | last1=Carraro | first1=Giovanni
 | last2=Anthony-Twarog | first2=Barbara J. | last3=Costa
 | first3=Edgardo | last4=Jones | first4=Bryce J. | last5=Twarog | first5=Bruce A.
 | journal=The Astronomical Journal
 | volume=142 | issue=4 | id=127 | pages=18
 | date=October 2011 | doi=10.1088/0004-6256/142/4/127
 | arxiv=1108.0587 | bibcode=2011AJ....142..127C | s2cid=119099798 }}</ref>

<ref name=Cantat-Gaudin_Anders_2020>{{cite journal
 | title=Clusters and mirages: cataloguing stellar aggregates in the Milky Way
 | last1=Cantat-Gaudin | first1=T. | last2=Anders | first2=F.
 | journal=Astronomy & Astrophysics
 | volume=633 | id=A99 | pages=22
 | date=January 2020 | doi=10.1051/0004-6361/201936691
 | arxiv=1911.07075 | bibcode=2020A&A...633A..99C | s2cid=208138247 }}</ref>

<ref name="ned">{{cite web
  | title=NASA/IPAC Extragalactic Database
  | work=Results for NGC 5749
  | url=http://nedwww.ipac.caltech.edu/
  | access-date=2007-04-06}}</ref>

<ref name=SIMBAD>{{cite simbad
 | title=NGC 5822 | access-date=2021-12-29 }}</ref>

}}

==External links==
* {{commons category-inline}}
* {{WikiSky}}

{{Sky|15|04|21.2|-|54|23|47|2990}}
{{Ngc60|state=collapsed}}
{{Lupus (constellation)}}

[[Category:Open clusters]]
[[Category:Lupus (constellation)]]
[[Category:NGC objects|5822]]