View source for Astronomy:IC 2602

{{Short description|Open cluster in the constellation Carina}}
{{Infobox open cluster
|name=IC 2602
|image=[[File:The Southern Pleiades (IC 2602).jpg|250px]]
|caption=
|epoch=[[Astronomy:J2000|J2000]]
|constellation=[[Astronomy:Carina (constellation)|Carina]]|ra={{RA|10|42|57.5}}<ref name=ned>{{cite web|url=http://nedwww.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=IC+2602&extend=no&out_csys=Equatorial&out_equinox=J2000.0&obj_sort=RA+or+Longitude&of=pre_text&zv_breaker=30000.0&list_limit=5&img_stamp=YES|title=NED results for object IC 2602|access-date=23 January 2017|publisher=[[Organization:National Aeronautics and Space Administration|National Aeronautics and Space Administration]] / Infrared Processing and Analysis Center }}</ref>
|dec={{DEC|-64|23|39}}
|dist_pc=149 pc
|dist_ly=486 ly<ref name="SIMBAD"/>
|appmag_v=1.9<ref name="seds">{{cite web |title=IC 2602 - SEDS Messier Database |url=https://spider.seds.org/ngc/ngc.cgi?IC+2602 |access-date=23 January 2016}}</ref>
|size_v=50{{prime}} × 50{{prime}}
|mass_msol=
|age=13.7 M.yr<sup>−1</sup>
|notes=
|names=Theta Carinae Cluster, [[Astronomy:Caldwell catalogue|Caldwell]] 102, [[Astronomy:Collinder catalogue|Cr]] 229, [[Biography:Philibert Jacques Melotte|Mel]] 102, VDBH 103<ref name=SIMBAD>{{cite simbad|title=IC 2602}}</ref>
}}
'''IC 2602''' (also known as the '''Southern Pleiades''', '''Theta Carinae Cluster''', or '''Caldwell 102''')<ref>{{Cite book |last=O'Meara |first=Stephen James |url=https://books.google.com/books?id=evkODQAAQBAJ&dq=deep+sky+companions+caldwell+objects+Southern+Pleiades%2C+Theta+Carinae+Cluster%2C+or+Caldwell+102%29&pg=PA467 |title=Deep-Sky Companions: The Caldwell Objects |date=2016-09-26 |publisher=Cambridge University Press |isbn=978-1-316-03353-1 |language=en}}</ref> is an [[Astronomy:Open cluster|open cluster]] in the [[Astronomy:Constellation|constellation]] [[Astronomy:Carina (constellation)|Carina]]. Discovered by Abbe Lacaille in 1751 from {{wipe|South Africa}}, the cluster is easily visible to the [[Astronomy:Naked eye|unaided eye]], and is one of the nearest star clusters, centred about 149 parsecs (486 [[Astronomy:Light-year|light-years]]) away from [[Astronomy:Earth|Earth]].

==Description==
IC 2602 has a total [[Astronomy:Apparent magnitude|apparent magnitude]] of 1.9,<ref name="seds"/> and contains about 75 stars. It is the third-brightest open cluster in the sky, following the [[Astronomy:Hyades (star cluster)|Hyades]] and the [[Astronomy:Pleiades|Pleiades]]. Its apparent diameter is about 50 arcminutes.

IC 2602 is likely about the same age as the [[Astronomy:Open cluster|open cluster]] [[Astronomy:IC 2391|IC 2391]],<ref name="Staffer19972">{{cite journal |author=Stauffer, J.R. |last2=Hartmann |first2=Lee W. |last3=Prosser |first3=Charles F. |last4=Randich |first4=Sofia |last5=Balachandran |first5=Suchitra |last6=Patten |first6=Brian M. |last7=Simon |first7=Theodore |last8=Giampapa |first8=Mark |display-authors=1 |date=1997 |title=Rotational Velocities and Chromospheric/Coronal Activity of Low-Mass Stars in the Young Open Clusters IC 2391 and IC 2602 |journal=Astrophysical Journal |volume=479 |issue=2 |pages=776 |bibcode=1997ApJ...479..776S |doi=10.1086/303930 |doi-access=free}},</ref> which has a [[Astronomy:Lithium depletion boundary|lithium depletion boundary]] age of 50 million years old,<ref name="Barrado20022">{{cite journal |last1=Barrado y Navascues |first1=D |last2=Stauffer |first2=J.R. |last3=Jayawardhana |first3=R. |date=2002 |title=Spectroscopy of Very Low Mass Stars and Brown Dwarfs in IC 2391: Lithium Depletion and Hα Emission |journal=Astrophysical Journal |volume=614 |issue=1 |pages=386–397 |arxiv=astro-ph/0406436 |bibcode=2004ApJ...614..386B |doi=10.1086/423485|s2cid=208867491 }}</ref> though the age estimated from its Hertzsprung-Russell diagram is about 13.7 million years.<ref name="webda20172">{{cite web |title=WEBDA page for open cluster IC 2602 |url=http://cbat.eps.harvard.edu/CBAT_M31.html |access-date=2017-04-11 |publisher=WEBDA}}</ref> IC 2602 is thought to form  part of the Lower [[Astronomy:Scorpius–Centaurus association|Scorpius–Centaurus association]].<ref name="Whiteoak19612">{{cite journal |last1=Whiteoak |first1=J.B. |date=1961 |title=A study of the galactic cluster IC 2602. I. A photoelectric and spectroscopic investigation |journal=Monthly Notices of the Royal Astronomical Society |volume=123 |pages=245–256 |bibcode=1961MNRAS.123..245W |doi=10.1093/mnras/123.3.245 |doi-access=free}}</ref><ref name="Blaauw19642">{{cite journal |last1=Blaauw |first1=A. |date=1964 |title=The O Associations in the Solar Neighborhood |journal=Annual Review of Astronomy and Astrophysics |volume=2 |pages=213–246 |bibcode=1964ARA&A...2..213B |doi=10.1146/annurev.aa.02.090164.001241}}</ref>

== Components ==
Theta Carinae is the brightest [[Astronomy:Star|star]] within the open cluster, with the [[Astronomy:Apparent magnitude|apparent]] visual magnitude of +2.74.<ref>{{Cite web |title=Theta Carinae |url=https://simbad.u-strasbg.fr/simbad/sim-id |access-date=2022-12-12 |website=simbad.u-strasbg.fr}}</ref> Theta Carinae is part of the [[Astronomy:Asterism|asterism]] known as the [[Astronomy:Diamond Cross|Diamond Cross]], which is often mistaken for the Southern Cross asterism in the constellation of [[Astronomy:Crux|Crux]].

[[Astronomy:PP Carinae|p Carinae]] (PP Carinae) is another third-magnitude star known to be a member of IC 2602, although it lies well outside the main visible grouping of stars. p Carinae exhibits a variable apparent magnitude ranging from 3.22 to 3.55.

All other members the cluster are of the fifth magnitude and fainter, but several are naked-eye objects, including HR 4196 (V518 Car), HR 4204, [[Astronomy:HD 93194|HD 93194]], HR 4219, HR 4220, HR 4222, HD 92536, HD 93738, and V364 Carinae.

An [[Astronomy:Exoplanet|exoplanet]] has been found orbiting the star TOI-837 in this cluster.<ref name="Bouma2020"/>

{| class="wikitable sortable"
|+'''IC 2602 Brightest Stars'''
!Designation
![[Astronomy:Apparent magnitude|Apparent magnitude]]<ref name=":0">{{Cite web |title=Gaia Archive |url=https://gea.esac.esa.int/archive/ |access-date=2022-12-24 |website=gea.esac.esa.int}}</ref>
![[Astronomy:Stellar classification|Stellar classification]]<ref>{{Cite web |title=Theta Carinae |url=https://simbad.u-strasbg.fr/simbad/sim-id |access-date=2022-12-24 |website=simbad.u-strasbg.fr}}</ref>
!Distance (pc)
|-
|[[Astronomy:Theta Carinae|Theta Carinae]]
|2.735
|style="background:#{{Color temperature|20000|hexval}};"|B0Vp
|142<ref>{{Cite journal |last=Whitman |first=Alan |date=June 1998 |title=At The Eyepiece: Eclipse-Chasing Perfection - The Caribbean |journal=Journal of the Royal Astronomical Society of Canada |volume=92 |page=158 |bibcode=1998JRASC..92..158W}}</ref>
|-
|[[Astronomy:PP Carinae|p Carinae]] (PP Carinae)
|3.247
|style="background:#{{Color temperature|20000|hexval}};"|B4Vne
|104.645<ref name=":0" />
|-
|HR 4204
|5.719
|style="background:#{{Color temperature|20000|hexval}};"|B3IV/V
|309.598<ref>{{Cite web |title=Catalogues - Hipparcos - Cosmos |url=https://www.cosmos.esa.int/web/hipparcos/catalogues |access-date=2022-12-24 |website=www.cosmos.esa.int}}</ref><ref>Equated from parallax in milliarcseconds (mas).</ref>
|-
|HR 4219
|5.297
|style="background:#{{Color temperature|20000|hexval}};"|B6Vnn
|156.674<ref name=":0" />
|-
|HR 4222
|4.807
|style="background:#{{Color temperature|20000|hexval}};"|B4V
|154.007<ref name=":0" />
|-
|HD 92536
|6.313
|style="background:#{{Color temperature|20000|hexval}};"|B8V
|156.823<ref name=":0" />
|-
|[[Astronomy:HD 93194|HD 93194]]
|4.777
|style="background:#{{Color temperature|20000|hexval}};"|B3/5Vn
|169.146<ref name=":0" />
|-
|HD 93738
|8.571
|style="background:#{{Color temperature|20000|hexval}};"|B9.5V
|417.168<ref name=":0" />
|-
|V364 Carinae
|5.465
|style="background:#{{Color temperature|8750|hexval}};"|ApSi
|160.013<ref name=":0" />
|-
|[[Astronomy:V518 Carinae|V518 Carinae]]
|4.758
|style="background:#{{Color temperature|20000|hexval}};"|B3V
|140.634<ref name=":0" />
|}

== History ==
IC 2602 was first discovered by French [[Astronomy:Astronomer|astronomer]] and [[Religion:Abbot|abbot]] Nicolas-Louis de Lacaille on March 3, 1751 while in Cape of Good Hope, {{wipe|South Africa}}.<ref>{{Cite journal |last=Jones |first=K. G. |date=March 1969 |title=The Search for the Nebulae - VI |journal=Journal of the British Astronomical Association |volume=79 |page=213 - 222 |bibcode=1969JBAA...79..213J}}</ref> In Lacaille's initial discovery, he classified Theta Carinae (referred as "Theta Navis", or alternatively "Theta Argus"{{Citation needed|date=December 2022}}) as a [[Astronomy:Magnitude|third magnitude]] star, whilst citing the cluster's resemblance to the northern Pleiades.

== Observation ==
Positioned at a [[Declination|declination]] of -64º on the night sky,<ref name="ned2">{{cite web |title=NED results for object IC 2602 |url=http://nedwww.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=IC+2602&extend=no&out_csys=Equatorial&out_equinox=J2000.0&obj_sort=RA+or+Longitude&of=pre_text&zv_breaker=30000.0&list_limit=5&img_stamp=YES |access-date=23 January 2017 |publisher=[[Organization:National Aeronautics and Space Administration|National Aeronautics and Space Administration]] / Infrared Processing and Analysis Center}}</ref> IC 2602 is most clearly visible from the [[Earth:Southern Hemisphere|southern hemisphere]], and appears [[Astronomy:Circumpolar star|circumpolar]] from southern [[Earth:Subtropics|subtropics]] and [[Earth:Temperate climate|temperate climates]]; the cluster is observable from a limited selection of [[Earth:Northern Hemisphere|north hemispherical]] regions, mainly [[Earth:Tropical rainforest|tropical]] areas.{{efn|IC 2602 is located at a declination of {{val|-64|ul=°}}, which equates to an angular distance of 26º from the [[Astronomy:Celestial pole|south celestial pole]].}} IC 2602 is identifiable a few degrees south of the southern [[Astronomy:Milky Way|Milky Way]], surrounded by various fifth and sixth magnitude stars. To the unaided eye, several faint stars are distinguishable to the east of the blue Theta Carinae.

==Notes==
{{notelist}}

==References==
{{reflist|refs=

<ref name="Bouma2020">{{cite journal |last1=Bouma |first1=L. G. |last2=Hartman |first2=J. D. |display-authors=0 |date=November 2020 |title=Cluster Difference Imaging Photometric Survey. II. TOI 837: A Young Validated Planet in IC 2602 |journal=[[Astronomy:The Astronomical Journal|The Astronomical Journal]] |volume=160 |issue=5 |pages=239 |doi=10.3847/1538-3881/abb9ab |arxiv=2009.07845 |bibcode=2020AJ....160..239B |doi-access=free }}</ref>

}}

== External links ==


* [http://messier.seds.org/xtra/ngc/i2602.html The Southern Pleaides @ SEDS IC objects pages]
* [http://www.starrynightphotos.com/southern_sky/southern_pleiades_ic_2602.htm Image Southern Pleiades(IC 2602)]
{{Caldwell catalogue}}
{{sky|10|42|56|-|64|23|42|479}}

{{DEFAULTSORT:IC 2602}}
[[Category:IC 2602| ]]
[[Category:Carina (constellation)]]
[[Category:Open clusters]]
[[Category:Caldwell objects|102b]]

{{Sourceattribution|IC 2602}}