View source for NGC 3603

{{Short description|Open cluster in the constellation Carina}}

{{Infobox nebula
 |name          = NGC 3603
 |image         = [[File:Stellar nursery NGC 3603.jpg|300px]]
 |caption       = NGC 3603 in visible and near infrared light
 |credit        =
 |type          = Giant molecular cloud
 |type2         = [[H II region]]
 |epoch         = [[J2000]]
 |subtype       =
 |class         =
 |ra            = {{RA|11|15|23}}<ref name=kharchenko2013>{{cite journal|bibcode=2013A&A...558A..53K|title=Global survey of star clusters in the Milky Way. II. The catalogue of basic parameters|journal=Astronomy & Astrophysics|volume=558|pages=A53|last1=Kharchenko|first1=N. V.|last2=Piskunov|first2=A. E.|last3=Schilbach|first3=E.|last4=Röser|first4=S.|last5=Scholz|first5=R.-D.|year=2013|doi=10.1051/0004-6361/201322302|arxiv = 1308.5822 |s2cid=118548517 }}</ref>
 |dec           = {{DEC|-61|15|00}}<ref name=kharchenko2013/>
 |dist_ly       =
 |dist_pc       = 6,900<ref name=pang2013>{{cite journal|bibcode=2013ApJ...764...73P|title=On the Origin of Mass Segregation in NGC 3603|journal=The Astrophysical Journal|volume=764|issue=1|pages=73|last1=Pang|first1=Xiaoying|last2=Grebel|first2=Eva K.|last3=Allison|first3=Richard J.|last4=Goodwin|first4=Simon P.|last5=Altmann|first5=Martin|last6=Harbeck|first6=Daniel|last7=Moffat|first7=Anthony F. J.|last8=Drissen|first8=Laurent|year=2013|doi=10.1088/0004-637X/764/1/73|arxiv = 1212.4566 |s2cid=119199840 }}</ref>
 |dist_z        =
 |appmag_v      = 9.1<ref name=ngc>{{cite journal|bibcode=1988cngc.book.....S|title=The complete new general catalogue and index catalogues of nebulae and star clusters by J. L. E. Dreyer|journal=Cambridge: Sky Publishing Corporation and Cambridge University Press|last1=Sinnott|first1=Roger W.|year=1988}}</ref>
 |appdia        = 12.0'<ref name=ngc/>
 |size_v        =
 |constellation = Carina
 |radius_ly     =
 |radius_pc     =
 |dimensions    =
 |absmag_v      =
 |notes         =
 |names         = [[Gum Nebula|Gum]] 38b, [[Collinder catalogue|Collinder]] 244, RCW 57
}}
'''NGC 3603''' is a [[nebula]] situated in the [[Carina–Sagittarius Arm]] of the [[Milky Way]] around 20,000 [[light-year]]s away from the [[Solar System]].  It is a massive [[H II region]] containing a very compact [[open cluster]] (probably a [[super star cluster]]) [[HD 97950]].

==Observations==
[[File:Star formation in the southern Milky Way.jpg|thumb|left|upright=1.6|NGC 3603 (left) and [[NGC 3576]] are star formation regions in the southern [[Milky Way]].]]
NGC 3603 was observed by [[John Herschel]] on 14 March 1834 during his [[John Herschel#Visit to South Africa|visit to South Africa]], who remarked that it was "a very remarkable object...perhaps a [[globular cluster]]". Herschel catalogued it as [[nebula]] 3334 in his ''Results of Astronomical Observations made at the Cape of Good Hope'', published in 1847. In 1864 the [[Royal Society]] published his ''[[General Catalogue of Nebulae and Clusters]]'', where he listed it as number 2354. It was subsequently incorporated into the ''[[New General Catalogue]]'' as by [[J. L. E. Dreyer]] as NGC 3603.<ref name=sher1965>{{cite journal
  |last=Sher |first=D.
  |title=The Curious History of NGC 3603
  |journal=Journal of the Royal Astronomical Society of Canada
  |volume=59 |pages=67–70 |year=1965
  |bibcode=1965JRASC..59...67S}}</ref>

The central cluster was catalogued as the star [[HD 97950]], but has long been recognised as nebulous or multiple.<ref name=sher1965/>  It was also noted for having an unusual emission spectrum and the spectral type was given as Oe in the [[Henry Draper Catalogue]].  This was later refined to WN5 + O as the emission was recognised as characteristic of a [[Wolf–Rayet star]].<ref name=sher1965/>  Eventually, the cluster would be resolved and found to contain three of the [[List of most massive stars|most massive]] and [[List of most luminous stars|most luminous]] stars known, as well as a number of luminous O class stars and many fainter stars.<ref name=harayama2008>{{cite journal|bibcode=2008ApJ...675.1319H|title=The Initial Mass Function of the Massive Star-forming Region NGC 3603 from Near-Infrared Adaptive Optics Observations|journal=The Astrophysical Journal|volume=675|issue=2|pages=1319|last1=Harayama|first1=Y.|last2=Eisenhauer|first2=F.|last3=Martins|first3=F.|year=2008|doi=10.1086/524650|arxiv = 0710.2882 |s2cid=17905999 }}</ref>

==Features==
[[File:NGC_3603_Cluster.jpg|thumb|left|upright=1.2|Image of the NGC 3603 region were obtained in three near-IR filter bands (Js, H and Ks) with the [[Very Large Telescope|ISAAC instrument at the ANTU telescope]]]]
NGC 3603 is the most massive visible cloud of glowing [[gas]] and [[Plasma (physics)|plasma]], known as a [[H II region]], in the Milky Way.<ref>{{cite journal|bibcode=1999Msngr..98...46B|title=VLT/ISAAC and HST/WFPC2 observations of NGC 3603|journal=The Messenger|volume=98|pages=46|last1=Brandl|first1=B.|last2=Brandner|first2=W.|last3=Grebel|first3=E. K.|last4=Zinnecker|first4=H.|year=1999}}</ref>  The central [[star cluster]] is the densest concentration of very massive stars known in the galaxy. Strong [[ultraviolet]] [[electromagnetic radiation|radiation]] and [[stellar wind]]s have cleared the gas and dust, giving an unobscured view of the cluster.<ref name=drissen1995>{{cite journal|bibcode=1995AJ....110.2235D|title=The Dense Galactic Starburst NGC 3603. I. HST/FOS Spectroscopy of Individual Stars in the Core and the source of Ionization and Kinetic Energy|journal=Astronomical Journal |volume=110|pages=2235|last1=Drissen|first1=Laurent|last2=Moffat|first2=Anthony F. J.|last3=Walborn|first3=Nolan R. |author3-link=Nolan R. Walborn |last4=Shara|first4=Michael M.|year=1995|doi=10.1086/117684|doi-access=free}}</ref>

Three prominent [[Wolf–Rayet stars]] have been detected within the cluster, all originally unresolved and known as the single star HD 97950. The brightest of the three, [[NGC 3603-A1|HD 97950A1]] (or NGC 3603-A1) is actually a [[binary star|pair]] of Wolf–Rayet stars that orbit around each other once every 3.77 days. The primary is an estimated mass {{Solar mass|120}}, while its companion is {{Solar mass|92}}.  The star designated [[NGC 3603-B|HD 97950B]] is a single star more massive and more luminous than either of the individual members of HD 97950A1. It is 2,880,000 times as luminous as the sun and 132 times as massive.<ref name=crowther>{{Cite journal |last1=Crowther |first1=P. A. |last2=Schnurr |first2=O. |last3=Hirschi |first3=R. |last4=Yusof |first4=N. |last5=Parker |first5=R. J. |last6=Goodwin |first6=S. P. |last7=Kassim |first7=H. A.  |year=2010 |title=The R136 star cluster hosts several stars whose individual masses greatly exceed the accepted 150 M<sub>⊙</sub> stellar mass limit |journal=Monthly Notices of the Royal Astronomical Society|volume=408 |issue=2 |pages=731 |arxiv=1007.3284 |bibcode=2010MNRAS.408..731C |doi=10.1111/j.1365-2966.2010.17167.x|doi-access=free |s2cid=53001712 }}</ref>

NGC 3603 is visible in the telescope as a small rather insignificant nebulosity with a yellowish tinge due to the effects of interstellar absorption. In the mid-1960s, optical studies combined with radio astronomical observations showed it to be an extremely strong thermal radio source. Later observations of other galaxies introduced the concept of [[starburst region]]s, in some cases whole [[starburst galaxy|galaxies]], of extremely rapid star formation.  NGC 3603 is now considered to be such a region, and it has been compared by some authors to the larger cluster [[30 Doradus]], in the [[Large Magellanic Cloud]].<ref name=MTT>{{cite journal|bibcode=1989A&A...213...89M|title=The galactic giant H II region NGC 3603|journal=Astronomy and Astrophysics|volume=213|pages=89|last1=Melnick|first1=J.|last2=Tapia|first2=M.|last3=Terlevich|first3=R.|year=1989}}</ref>

[[Sher 25]], a B class supergiant, has long been thought to be a member of NGC 3603, but turns out to be a foreground star.<ref name=hessmaier>{{Cite journal |last=Weßmayer |first=D. |last2=Przybilla |first2=N. |last3=Ebenbichler |first3=A. |last4=Aschenbrenner |first4=P. |last5=Butler |first5=K. |date=2023-09-01 |title=The blue supergiant Sher 25 revisited in the Gaia era |url=https://ui.adsabs.harvard.edu/abs/2023A&A...677A.175W/abstract |journal=Astronomy and Astrophysics |volume=677 |pages=A175 |doi=10.1051/0004-6361/202347253 |bibcode=2023A&A...677A.175W |issn=0004-6361|arxiv=2308.06164 }}</ref> is surrounded by ejected material in an hourglass shape similar to that found for the supernova 1987A, and this has aroused intense interest in the future evolution of stars such as Sher 25.<ref name=hendry2008>{{cite journal|doi=10.1111/j.1365-2966.2008.13347.x|title=The blue supergiant Sher 25 and its intriguing hourglass nebula|journal=Monthly Notices of the Royal Astronomical Society|volume=388|issue=3|pages=1127|year=2008|last1=Hendry|first1=M. A.|last2=Smartt|first2=S. J.|last3=Skillman|first3=E. D.|last4=Evans|first4=C. J.|last5=Trundle|first5=C.|last6=Lennon|first6=D. J.|last7=Crowther|first7=P. A.|last8=Hunter|first8=I.|doi-access=free |bibcode=2008MNRAS.388.1127H|arxiv = 0803.4262 |s2cid=16802111 }}</ref>

Two of the most luminous young stars known are found within NGC 3603, but outside the central cluster.  [[WR 42e]] and NGC 3603 MTT 58 both have a spectral type of O2If*/WN6 indicating an extremely massive young star.  WR 42e is a possible runaway from a three-body encounter, while MTT 58 appears to still be embedded within its parental cocoon and is in a possible binary with an O3If star.<ref name=roman2013>{{cite journal|bibcode=2013MNRAS.433..712R|title=An O2 If*/WN6 star caught in the act in a compact H II region in the starburst cluster NGC 3603|journal=Monthly Notices of the Royal Astronomical Society|volume=433|issue=1|pages=712–718|last1=Roman-Lopes|first1=A.|year=2013|doi=10.1093/mnras/stt762|doi-access=free |arxiv = 1305.0851 }}</ref>

{| class="wikitable sortable"
|+ Prominent stars
|-
!MDS number
!MTT number
!Other names
!Spectral type
!m<sub>V</sub>
!M<sub>V</sub>
!Temperature
([[Kelvin|K]])
!Luminosity
('''{{solar luminosity|link=y}}''')
!Reference
|-
|30([[NGC 3603-A1|A1]])
|
|WR 43a (HSW 1)
|WN6h/WN6h
|11.18
| -7.8
|42,000/40,000
|2,455,000/1,514,000
|<ref name="crowther" /><ref name="moffat1994">{{cite journal|last1=Moffat|first1=Anthony F. J.|last2=Drissen|first2=Laurent|last3=Shara|first3=Michael M.|year=1994|title=NGC 3603 and its Wolf–Rayet stars: Galactic clone of R136 at the core of 30 Doradus, but without the massive surrounding cluster halo|journal=Astrophysical Journal|volume=436|pages=183|bibcode=1994ApJ...436..183M|doi=10.1086/174891|doi-access=free}}</ref><ref name="harayama2008" />
|-
|31(A2)
|
|HSW 4
|O3V
|12.53
| -6.9
|46,500
|1,500,000
|<ref name="moffat1994" /><ref name="harayama2008" />
|-
|26(A3)
|
|HSW 5
|O3III
|13.09
| -6.4
|46,500
|863,000
|<ref name="moffat1994" /><ref name="harayama2008" />
|-
|23([[NGC 3603-B|B]])
|
|WR 43b (HSW 2)
|WN6h
|11.33
| -7.9
|42,000
|2,884,000
|<ref name="crowther" /><ref name="harayama2008" />
|-
|18([[NGC 3603-C|C]])
|
|WR 43c (HSW 3)
|WN6h
|11.89
| -7.3
|44,000
|2,239,000
|<ref name="crowther" /><ref name="harayama2008" />
|-
|49(D1)
|
|
|O4V
|12.64
| -6.3
|44,000
|
|<ref name="massey2005">{{cite journal|last1=Massey|first1=Philip|last2=Puls|first2=Joachim|last3=Pauldrach|first3=A. W. A.|last4=Bresolin|first4=Fabio|last5=Kudritzki|first5=Rolf P.|last6=Simon|first6=Theodore|year=2005|title=The Physical Properties and Effective Temperature Scale of O-Type Stars as a Function of Metallicity. II. Analysis of 20 More Magellanic Cloud Stars and Results from the Complete Sample|journal=The Astrophysical Journal|volume=627|issue=1|pages=477–519|arxiv=astro-ph/0503464|bibcode=2005ApJ...627..477M|doi=10.1086/430417|s2cid=18172086}}</ref><ref name="moffat1994" /><ref name="harayama2008" />
|-
|50(D2)
|
|
|O5V
|12.74
| -6.2
|41,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|52(D3)
|
|
|O4V
|13.68
| -5.2
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|19(E)
|
|MMM 104
|O5.5III(f)
|12.83
| -6.1
|41,000
|1,038,000
|<ref name=melena2008>{{cite journal|bibcode=2008AJ....135..878M|title=The Massive Star Content of NGC 3603|journal=The Astronomical Journal|volume=135|issue=3|pages=878–891|last1=Melena|first1=Nicholas W.|last2=Massey|first2=Philip|last3=Morrell|first3=Nidia I.|last4=Zangari|first4=Amanda M.|year=2008|doi=10.1088/0004-6256/135/3/878|arxiv = 0712.2621 |s2cid=16765414}}</ref><ref name="massey2005" /><ref name="moffat1994" />
|-
|39(F)
|6
|
|O5V
|11.86
| -6.1
|41,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|61(G)
|10
|
|O5V
|12.74
| -6
|41,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|
|58
|WR 43-2
|O2If*/WN6
|14.76
| -5.7
|
|855,000
|<ref name="melena2008" /><ref name="roman2013"/>
|-
|
|
|[[WR 42e]]
|O2If*/WN6
|14.53
| -6.3
|
|1,300,000
|<ref name="melena2008" /><ref name="roman2012">{{cite journal|last1=Roman-Lopes|first1=A.|year=2012|title=A Galactic O2 If*/WN6 star possibly ejected from its birthplace in NGC 3603|journal=Monthly Notices of the Royal Astronomical Society: Letters|volume=427|issue=1|pages=L65–L69|arxiv=1209.1598|bibcode=2012MNRAS.427L..65R|doi=10.1111/j.1745-3933.2012.01346.x|doi-access=free |s2cid=118453639}}</ref>
|-
|29
|
|
|O4V
|13.68
| -5.2
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|27
|
|
|O4V
|13.07
| -5.8
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|25
|
|
|O4V
|13.01
| -5.9
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|40
|
|
|O3V
|13.33
| -5.7
|46,500
|718,000
|<ref name="melena2008" />
|-
|33
|
|
|O5V+OB?
|13.69
| -5.8
|
|
|<ref name="melena2008" /><ref name="massey2005" />
|-
|41
|
|
|O4V
|14.24
| -5.1
|44,000
|217,000
|<ref name="melena2008" />
|-
|42
|
|
|O3III
|12.99
| -6.1
|46,500
|946,000
|<ref name="melena2008" />
|-
|37
|
|
|O6.5V+?
|14.16
| -5
|
|
|<ref name="massey2005" /><ref name="harayama2008" />
|-
|38
|
|
|O3V
|13.21
| -5.9
|46,500
|497,000
|<ref name="melena2008" />
|-
|16
|
|
|O3V
|13.53
| -5.4
|46,500
|655,000
|<ref name="melena2008" />
|-
|43
|
|MMM 111
|O4V
|13.87
| -5
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|14
|
|
|O4V
|13.88
| -5
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|59
|
|
|O4V
|13.65
| -5.3
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|60
|
|
|O4V
|13.6
| -5.3
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|62
|
|
|O4V
|13.09
| -5.6
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|58
|
|MMM 101
|O6.5V((f))
|14.02
| -5.1
|37,000
|238,000
|<ref name="melena2008" />
|-
|51
|23
|Sher 56
|O4V(f)
|13.33
| -5.6
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|9
|
|MMM 108
|O5.5V
|13.71
| -5.5
|39,500
|377,000
|<ref name="melena2008" />
|-
|7
|26
|Sher 64
|O4V
|13.58
| -5.4
|44,000
|863,000
|<ref name="melena2008" /><ref name="MTT" />
|-
|22
|17
|Sher 57
|O5III(f)
|13.23
| -5.8
|41,000
|787,000
|<ref name="melena2008" /><ref name="MTT" />
|-
|1
|12
|Sher 23
|OC9.7Ia
|12.7
| -6.3
|30,250
|413,000
|<ref name="melena2008" />
|-
|2
|18
|Sher 22
|O3III(f)
|13.21
| -5.6
|46,500
|863,000
|<ref name="melena2008" />
|-
|48
|14
|Sher 18
|O3.5If
|12.65
| -6.4
|39,500
|1,644,000
|<ref name="melena2008" />
|-
|24
|11
|Sher 47
|O4V
|12.72
| -6.2
|44,000
|1,644,000
|<ref name="melena2008" />
|-
|20
|
|
|O4V
|13.98
|
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|76
|39
|Sher 54
|O6V
|14.57
| -4.6
|38,300
|150,000
|<ref name="melena2008" />
|-
|17
|
|MMM 116
|O4V
|14.1
|
|44,000
|
|<ref name="massey2005" /><ref name="harayama2008" />
|-
|36
|
|
|O6V
|14.52
| -4.2
|38,300
|114,000
|<ref name="melena2008" />
|-
|45
|
|
|O8V-III
|14.14
| -4.7
|33,700
|114,000
|<ref name="melena2008" />
|-
|4
|41
|Sher 49
|O7.5V
|14.67
| -4.6
|34,800
|114,000
|<ref name="melena2008" />
|-
|57
|
|
|O4V
|13.98
|
|44,000
|
|<ref name="massey2005" /><ref name="moffat1994" /><ref name="harayama2008" />
|-
|10
|
|MMM 117
|O6V
|14.17
| -5.1
|38,300
|238,000
|<ref name="melena2008" />
|-
|3
|32
|Sher 24
|O6V
|14.27
| -5
|38,300
|217,000
|<ref name="melena2008" />
|-
|
|51
|Sher 27
|O7.5V
|15.04
| -4
|34,800
|65,000
|<ref name="melena2008" />
|-
|
|15
|Sher 63
|O3.5III(f)
|13.41
| -5.6
|45,000
|597,000
|<ref name="melena2008" />
|-
|63
|40
|Sher 53
|O8.5V
|14.47
| -4.8
|32,700
|125,000
|<ref name="melena2008" />
|-
|73
|
|MMM 102
|O8.5V
|15.32
| -3.9
|32,700
|50,000
|<ref name="melena2008" />
|-
|
|47
|Sher 21
|O6V((f))
|14.75
| -4.6
|38,300
|150,000
|<ref name="melena2008" />
|-
|
|25
|Sher 19
|O3V
|12.61
| -6.2
|46,500
|497,000
|<ref name="melena2008" /><ref name="MTT" />
|-
|
|
|MMM 103
|O3V((f))
|13.09
| -5.7
|46,500
|718,000
|<ref name="melena2008" />
|-
|
|
|MMM 109
|O7V
|13.85
| -4.9
|36,000
|180,000
|<ref name="melena2008" />
|}

==References==
{{Reflist}}

==External links==
{{commons category}}
* [http://hubblesite.org/newscenter/archive/releases/2007/34/ Hubble Space Telescope: Star Cluster Bursts into Life in New Hubble Image]
* [http://www.eso.org/public/news/eso1005/ European Southern Observatory: The Stars behind the Curtain]

{{Ngc40}}
{{RCW}}
{{Gum catalogue}}
{{Carina (constellation)}}

{{DEFAULTSORT:Ngc 3603}}
[[Category:NGC 3603| ]]
[[Category:Carina (constellation)]]
[[Category:H II regions]]
[[Category:NGC objects|3603]]
[[Category:Star-forming regions]]
[[Category:Carina–Sagittarius Arm]]