View source for IC 4651

{{Short description|Open star cluster in the constellation Ara}}
{{Infobox open cluster|
| image = [[File:The rich star cluster IC 4651.jpg|300px|The rich star cluster IC 4651]]
|caption = Open cluster IC 4651 taken by the Wide Field Imager (WFI) camera, on the MPG/ESO 2.2-meter telescope at ESO’s [[La Silla Observatory]] in Chile.<ref>{{cite web|title=Sibling Stars|url=http://www.eso.org/public/news/eso1534/|access-date=19 August 2015}}</ref>
| name = IC 4651
| type = [[Open Cluster]]
| epoch = [[J2000]]
| ra = {{RA|17|24|49}}<ref name=apj619/>
| dec = {{DEC|−49|56|00}}<ref name=apj619/>
| dist_ly = 2,900 [[light years|ly]]
| dist_pc = 888<ref name=aaa389/>&nbsp;[[parsecs|pc]]
| appmag_v = 
| size_v = 10.0' ([[arcmin]])
| radius_ly = 
| absmag_v  = 
| constellation = [[Ara (constellation)|Ara]]
| notes = 
| names = [[Collinder catalogue|Cr]] 327, [[Melotte catalogue|Mel]] 169
}}

'''IC 4651''' is an [[open cluster]] of [[star]]s located about 2,900 [[light year]]s distant in the [[constellation]] [[Ara (constellation)|Ara]]. It was first catalogued by [[John Louis Emil Dreyer]] in his 1895 version of the ''[[Index Catalogue]]''.<ref name=mras51/> This is an intermediate age cluster that is {{nowrap|1.2 ± 0.2}} billion years old.<ref name=aaa475/> Compared to the Sun, the members of this cluster have a higher [[abundance of the chemical elements]] other than [[hydrogen]] and [[helium]].<ref name=aaa424/> The combined mass of the active stars in this cluster is about 630 times the [[mass of the Sun]].<ref name=aaa386/>

The currently known active stars in this cluster form only about 7% of the cluster's original mass. Of the remainder, about 35% of the mass consists of stars that have evolved into [[white dwarf]]s or other [[stellar remnant]]s. The remainder of lost mass consists of stars that have migrated away from the main body of the cluster or have been lost completely.<ref name=aaa386/>

The star IC 4651 9122 displays [[radial velocity]] variations suggesting the presence of a planetary companion, though stellar activity cannot be completely ruled out.<ref name="Leão2018"/><ref name="DelgadoMena2018"/><ref name="DelgadoMena2023"/>

==References==
{{reflist|refs=

<ref name="aaa389">{{cite journal |author1=Dias, W.S. |author2=Alessi, B.S. |author3=Moitinho, A. |author4=Lepine. J.R.D. | title=New catalog of optically visible open clusters and candidates | journal=Astronomy and Astrophysics | volume=389 | pages=871–873 |date=July 2002 |issue=3 | doi=10.1051/0004-6361:20020668 | bibcode=2002A&A...389..871D |arxiv = astro-ph/0203351 |s2cid=18502004 }} Note: see the [[VizieR]] catalogue [http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=B/ocl B/ocl].</ref>

<ref name="mras51">{{cite journal | last=Dreyer | first=J. L. E. | title=Index Catalogue of Nebulae found in the years 1888 to 1894, with Notes and Corrections to the New General Catalogue | journal=Memoirs of the Royal Astronomical Society | volume=51 | pages=185–228 | year=1895 | bibcode=1895MmRAS..51..185D }}</ref>

<ref name="apj619">{{cite journal |author1=Xin, Y. |author2=Deng, L. | title=Blue Stragglers in Galactic Open Clusters and Integrated Spectral Energy Distributions | journal=The Astrophysical Journal | volume=619| issue=2 | pages=824–838 |date=February 2005
| doi=10.1086/426681 | bibcode=2005ApJ...619..824X |arxiv = astro-ph/0410325 |s2cid=2087723 }}</ref>

<ref name="aaa475">{{cite journal 
 | display-authors=1 | last1=Biazzo | first1=K.
 | last2=Pasquini | first2=L. | last3=Girardi | first3=L.
 | last4=Frasca | first4=A. | last5=da Silva | first5=L.
 | last6=Setiawan | first6=J. | last7=Marilli | first7=E.
 | last8=Hatzes | first8=A. P. | last9=Catalano | first9=S.
 | title=Deriving temperature, mass, and age of evolved stars from high-resolution spectra. Application to field stars and the open cluster IC 4651
 | journal=Astronomy and Astrophysics | arxiv=0704.3192
 | volume=475 | issue=3 | date=December 2007 | pages=981–989
 | doi=10.1051/0004-6361:20077374 | bibcode=2007A&A...475..981B | s2cid=14293731 }}</ref>

<ref name="aaa424">{{cite journal | author=Pasquini, L. |display-authors=etal | title=Detailed chemical composition of the open cluster IC 4651: The iron peak, α elements, and Li | journal=Astronomy and Astrophysics | volume=424 | pages=951–963 |date=September 2004 | doi=10.1051/0004-6361:20040240 | bibcode=2004A&A...424..951P |arxiv = astro-ph/0406113 |s2cid=605163 }} This source gives a [[metallicity]] value of <math>\begin{smallmatrix}\left[\frac{Fe}{H}\right]\ =\ +0.10\ \pm\ 0.03\end{smallmatrix}</math>, which is equivalent to 125% of the Sun's abundance of Iron.</ref>

<ref name="aaa386">{{cite journal |author1=Meibom, S. |author2=Andersen, J. |author3=Nordström, B. | title=Critical tests of stellar evolution in open clusters. III. Stellar population and dynamical evolution of IC 4651 | journal=Astronomy and Astrophysics | volume=386 | pages=187–203 |date=April 2002 | doi=10.1051/0004-6361:20020183 | bibcode=2002A&A...386..187M |url=http://lup.lub.lu.se/record/118548 | doi-access=free }}</ref>

<ref name="Leão2018">{{cite journal |last1=Leão |first1=I. C. |last2=Canto Martins |first2=B. L. |display-authors=etal |date=December 2018 |title=Incidence of planet candidates in open clusters and a planet confirmation |journal=[[Astronomy & Astrophysics]] |volume=620 |issue= |pages=A139 |doi=10.1051/0004-6361/201833123 |arxiv=1807.03196 |bibcode=2018A&A...620A.139L}}</ref>

<ref name="DelgadoMena2018">{{cite journal |last1=Delgado Mena |first1=E. |last2=Lovis |first2=C. |display-authors=etal |date=November 2018 |title=Planets around evolved intermediate-mass stars. II. Are there really planets around IC 4651 No. 9122, NGC 2423 No. 3, and NGC 4349 No. 127? |journal=[[Astronomy & Astrophysics]] |volume=619 |issue= |pages=A2 |doi=10.1051/0004-6361/201833152 |arxiv=1807.09608 |bibcode=2018A&A...619A...2D |s2cid=119483881}}</ref>

<ref name="DelgadoMena2023">{{cite journal |last1=Delgado Mena |first1=E. |last2=Gomes da Silva |first2=J. |display-authors=etal |date=November 2023 |title=Planets around evolved intermediate-mass stars. III. Planet candidates and long-term activity signals in six open clusters |journal=[[Astronomy & Astrophysics]] |volume=679 |issue= |pages=A94 |doi=10.1051/0004-6361/202346890 |arxiv=2309.13589 |bibcode=2023A&A...679A..94D}}</ref>

}} <!-- End of reflist -->

== External links ==
* {{commonscat-inline}}


{{Ara (constellation)}}

[[Category:Open clusters]]
[[Category:IC objects|4651]]
[[Category:Ara (constellation)]]