RCW 38

{{Infobox open cluster

| name = RCW 38

| image = Star cluster RCW 38.jpg

| caption = Nebulosity around the embedded star cluster in RCW 38

| epoch = J2000

| class =

| constellation = Vela

| ra = {{RA|08|59|05.52}}

| dec = {{DEC|−47|30|39.2}}

| dist_ly = {{cvt|1.7|kpc|ly|order=flip|lk=on}}

| dist_pc =

| appmag_v =

| size_v =

| mass_kg =

| mass_msol =

| radius_ly =

| v_hb =

| age =

| notes =

| names =

|}}

__NOTOC__

RCW 38 is a star-forming region in the southern constellation of Vela (known as the Sails). It includes an embedded HII region and a super star cluster. This region is located at a distance of approximately {{convert|1.7|kpc|ly|disp=out|lk=on|abbr=off}} from the Sun.

This is the youngest super star cluster in the Milky Way galaxy, with age estimates ranging from 0.1 to 1.0 Myr. It has around 10,000 member stars. The cluster member stars are still enshrouded within the dark cloud in which they were born. The star cluster is surrounded by clouds of brightly glowing gas and includes many protostars. Observations by the Chandra X-ray Observatory have revealed more than 800 X-ray emitting young stellar objects in the cluster. 139 infrared sources have been identified as variable, of which 47% are candidate young stellar objects. Jets emerging from young protostars drive further star formation in the surrounding cloud.

The cluster includes about 20 massive O-type stars concentrated in a volume a few parsecs across. The latter stars are having a dissipative effect on the surrounding molecular gas. Five bow shocks have been identified coming from these objects, driven by strong stellar winds. When these massive stars die, likely before the dispersal of the cluster, they will explode as supernovae. It is hypothesized that these O-type stars were formed by a collision of two molecular clouds. The primary cloud has a mass of {{val|3|e=4|u=solar mass}}, while the secondary cloud has {{val|2|e=3|u=solar mass}}.

In the infrared, the brightest star in this region is designated IRS 2. This is a binary star system consisting of two spectral type O5.5 stars. It is located at the heart of the cluster, and appears to lie at the center of the H II region. The second brightest source is a dust ridge designated IRS 1, positioned about {{val|0.1|u=pc}} to the west of IRS 2. Both sources are surrounded by a dust-free cavity about {{val|0.1|u=pc}} across.

RCW 38 includes Gum 22, Gum 23, and Gum 24.{{clarify|date=March 2025}}

Gallery

File:RCW38Location.png|The location of RCW 38 (circled in red)

File:The Young Stellar Cluster RCW 38 in X-ray.jpg|An X-ray view of the dense central star cluster

File:Billions of new neighbours?.jpg|Central part of RCW 38, showing some of the brown dwarf candidates detected within the cluster

File:Nebula around star cluster RCW 38.jpg|The wider region surrounding RCW 38

References

{{Reflist|refs=

{{cite journal

| title=X-Ray and Infrared Point Source Identification and Characteristics in the Embedded, Massive Star-Forming Region RCW 38

| last1=Wolk | first1=Scott J. | last2=Spitzbart | first2=Bradley D.

| last3=Bourke | first3=Tyler L. | last4=Alves | first4=João

| display-authors=1 | journal=The Astronomical Journal

| volume=132 | issue=3 | pages=1100–1125 | date=September 2006

| doi=10.1086/505704 | arxiv=astro-ph/0605096

| bibcode=2006AJ....132.1100W }}

{{cite book

| chapter=The Embedded Massive Star Forming Region RCW 38

| title=Handbook of Star Forming Regions, Volume II: The Southern Sky ASP Monograph Publications

| display-authors=1 | last1=Wolk | first1=S. J.

| last2=Bourke | first2=T. L. | last3=Vigil | first3=M.

| editor-last=Reipurth | editor-first=B.

| volume=5 | page=43 | date=2008

| publisher=Astronomical Society of the Pacific

| bibcode=2008hsf2.book..124W | isbn=978-1-58381-670-7 }}

{{cite web

| title=Star cluster RCW 38 | publisher=ESO

| url=http://www.eso.org/public/images/eso0929b/

| access-date=2025-03-16 }}

{{cite web

| title=Colourful Celestial Landscape

| last=Turner | first=Calum | date=July 11, 2018

| publisher=ESO Public Information Office

| location=Garching bei München, Germany

| url=https://www.eso.org/public/news/eso1823/?stream=science

| access-date=2025-03-16 }}

{{Cite book

| title=Astrophysical Data: Planets and Stars

| last=Lang | first=Kenneth R. | date=December 6, 2012

| publisher=Springer Science & Business Media

| isbn=978-1-4684-0640-5 | language=en

| url=https://books.google.com/books?id=0_EHCAAAQBAJ&q=IC+2944+rcw+60&pg=PA414 }}

{{cite journal

| title=Identifying young stars in massive star-forming regions for the MYStIX project

| display-authors=1 | last1=Broos | first1=Patrick S.

| last2=Getman | first2=Konstantin V. | last3=Povich | first3=Matthew S.

| last4=Feigelson | first4=Eric D. | last5=Townsley | first5=Leisa K.

| last6=Naylor | first6=Tim | last7=Kuhn | first7=Michael A.

| last8=King | first8=Robert R. | last9=Busk | first9=Heather A.

| journal=The Astrophysical Journal Supplement Series

| volume=209 | issue=2 | year=2013 | pages=32

| issn=0067-0049 | doi=10.1088/0067-0049/209/2/32

| arxiv=1309.4500 | bibcode=2013ApJS..209...32B

| s2cid=67827240 }}

{{cite web

| title=Billions of new neighbours?

| website=www.eso.org

| url=https://www.eso.org/public/images/potw1729a/

| access-date=17 July 2017}}

{{cite journal

| title=The Structure of the Star-forming Cluster RCW 38

| last1=Winston | first1=E. | last2=Wolk | first2=S. J.

| last3=Bourke | first3=T. L. | last4=Megeath | first4=S. T.

| last5=Gutermuth | first5=R. | last6=Spitzbart | first6=B.

| display-authors=1 | journal=The Astrophysical Journal

| volume=743 | issue=2 | at=id. 166 | date=December 2011

| doi=10.1088/0004-637X/743/2/166 | arxiv=1110.2660

| bibcode=2011ApJ...743..166W }}

{{cite journal

| title=Hidden power of near-infrared data for the study of young clusters: Illustrative case of RCW 38

| last=Ascenso | first=Joana

| journal=Astronomy & Astrophysics

| volume=662 | at=id. A31 | date=June 2022

| doi=10.1051/0004-6361/202142582 | arxiv=2203.01064

| bibcode=2022A&A...662A..31A }}

{{cite journal

| title=ALMA view of the Galactic super star cluster RCW 38 at 270 au resolution

| display-authors=1 | last1=Torii | first1=Kazufumi

| last2=Tokuda | first2=Kazuki | last3=Tachihara | first3=Kengo

| last4=Onishi | first4=Toshikazu | last5=Fukui | first5=Yasuo

| journal=Publications of the Astronomical Society of Japan

| volume=73 | issue=1 | pages=205–219 | date=February 2021

| doi=10.1093/pasj/psaa115 | arxiv=1907.07358

| bibcode=2021PASJ...73..205T }}

{{cite journal

| title=The Two Molecular Clouds in RCW 38: Evidence for the Formation of the Youngest Super Star Cluster in the Milky Way Triggered by Cloud-Cloud Collision

| last1=Fukui | first1=Y. | last2=Torii | first2=K.

| last3=Ohama | first3=A. | last4=Hasegawa | first4=K.

| last5=Hattori | first5=Y. | last6=Sano | first6=H.

| last7=Ohashi | first7=S. | last8=Fujii | first8=K.

| last9=Kuwahara | first9=S. | last10=Mizuno | first10=N.

| last11=Dawson | first11=J. R. | last12=Yamamoto | first12=H.

| last13=Tachihara | first13=K. | last14=Okuda | first14=T.

| last15=Onishi | first15=T. | last16=Mizuno | first16=A.

| display-authors=1 | journal=The Astrophysical Journal

| volume=820 | issue=1 | at=id. 26 | date=March 2016

| doi=10.3847/0004-637X/820/1/26 | doi-access=free | arxiv=1504.05391

| bibcode=2016ApJ...820...26F }}

{{cite journal

| title=Near-infrared variability in the star-forming region RCW 38

| display-authors=1 | last1=Dörr | first1=M.

| last2=Chini | first2=R. | last3=Haas | first3=M.

| last4=Lemke | first4=R. | last5=Nürnberger | first5=D.

| journal=Astronomy & Astrophysics

| volume=553 | at=id. A48 | date=May 2013

| doi=10.1051/0004-6361/201220311 | bibcode=2013A&A...553A..48D }}

{{cite journal

| title=Spitzer Observations of Bow Shocks and Outflows in RCW 38

| last1=Winston | first1=E. | last2=Wolk | first2=S. J.

| last3=Bourke | first3=T. L. | last4=Megeath | first4=S. T.

| last5=Gutermuth | first5=R. | last6=Spitzbart | first6=B.

| display-authors=1 | journal=The Astrophysical Journal

| volume=744 | issue=2 | at=id. 126 | date=January 2012

| doi=10.1088/0004-637X/744/2/126 | arxiv=1111.4413

| bibcode=2012ApJ...744..126W }}

}}

External links

{{cite simbad

| title=RCW 38

| access-date=2025-03-16

| postscript=. | mode = cs2 }}

Category:Vela (constellation)

Category:Open clusters

Category:Star-forming regions

RCW 38

Gallery

References

Further reading

External links