Editing Large Magellanic Cloud (section)

==X-ray sources==
[[File:A Starry Combination.jpg|thumb|Small and Large Magellanic Clouds over [[Paranal Observatory]]]]
No X-rays above background were detected from either cloud during the September 20, 1966, [[Nike-Tomahawk]] rocket flight nor that of two days later.<ref name=Chodil >{{cite journal |title=X-Ray Intensities and Spectra from Several Cosmic Sources |journal=[[The Astrophysical Journal]] |date=Oct 1967 |volume=150 |issue=10 |pages=57–65| bibcode=1967ApJ...150...57C |doi=10.1086/149312|last1=Chodil |first1=G |last2=Mark |first2=Hans |last3=Rodrigues |first3=R |last4=Seward |first4=F. D |last5=Swift |first5=C. D |doi-access=free }}</ref> The second took off from [[Johnston Atoll]] at 17:13 UTC and reached an apogee of {{Cvt|160|km}}, with spin-stabilization at 5.6 rps.<ref name=Seward >{{cite journal |doi=10.1086/149343 |title=Search for 8–80 KEV X-Rays from the Large Magellanic Cloud and the Crab Nebula |journal=The Astrophysical Journal |date=Nov 1967 |volume=150 |issue=11 |pages=405–12 |bibcode=1967ApJ...150..405S |last1=Seward |first1=F. D |last2=Toor |first2=A |doi-access=free }}</ref> The LMC was not detected in the X-ray range 8–80 keV.<ref name="Seward"/>

Another was launched from same atoll at 11:32 UTC on October 29, 1968, to scan the LMC for X-rays.<ref name=Mark/> The first discrete X-ray source in [[Dorado (constellation)|Dorado]] was at [[Right ascension|RA]] {{RA|05|20}} [[Declination|Dec]] {{Dec|-69}},<ref name=Mark >{{cite journal |doi=10.1086/180322 |title=Detection of X-rays from the large magellanic cloud |date=Mar 1969 |journal=Astrophysical Journal Letters |volume=155 |issue=3 |pages=L143–4 |bibcode=1969ApJ...155L.143M |last1=Mark |first1=Hans |last2=Price |first2=R |last3=Rodrigues |first3=R |last4=Seward |first4=F. D |last5=Swift |first5=C. D }}</ref><ref name=Lewin >{{cite journal |title=Search for X-rays from the Large and Small Magellanic Clouds |date=1968 |journal=Nature |volume=220 |pages=249–250 |bibcode = 1968Natur.220..249L |doi = 10.1038/220249b0 |issue=5164|last1=Lewin |first1=W. H. G |last2=Clark |first2=G. W |last3=Smith |first3=W. B |s2cid=4187949 }}</ref> and it was the Large Magellanic Cloud.<ref name="Dolan">{{Cite journal |last=Dolan |first=Joseph F. |date=April 1970 |title=A Catalogue of Discrete Celestial X-Ray Sources |journal=[[The Astronomical Journal]] |volume=75 |issue=4 |pages=223 |bibcode=1970AJ.....75..223D |doi=10.1086/110966}}</ref> This X-ray source extended over about 12° and is consistent with the Cloud. Its emission rate between 1.5–10.5 keV for a distance of 50 kpc is {{val|4|e=38|ul=ergs}}/s.<ref name=Mark/> An [[X-ray astronomy]] instrument was carried aboard a [[Thor (rocket family)|Thor missile]] launched from the same atoll on September 24, 1970, at 12:54 UTC and altitudes above {{Cvt|300|km}}, to search for the [[Small Magellanic Cloud]] and to extend observation of the LMC.<ref name=PriceThor>{{cite journal |doi=10.1086/180773 |title=X-Rays from the Magellanic Clouds |journal=The Astrophysical Journal |date=Aug 1971 |volume=168 |issue=8 |pages=L7–9 |bibcode=1971ApJ...168L...7P |last1=Price |first1=R. E |last2=Groves |first2=D. J |last3=Rodrigues |first3=R. M |last4=Seward |first4=F. D |last5=Swift |first5=C. D |last6=Toor |first6=A |doi-access=free }}</ref> The source in the LMC appeared extended and contained star [[Epsilon Doradus|ε Dor]]. The X-ray luminosity (L<sub>x</sub>) over the range 1.5–12 keV was {{val|6|e=31|ul=W}} ({{val|6|e=38|u=erg/s}}).<ref name="PriceThor"/>

The Large Magellanic Cloud (LMC) appears in the constellations [[Mensa (constellation)|Mensa]] and [[Dorado]]. LMC X-1 (the first X-ray source in the LMC) is at [[Right ascension|RA]] {{RA|05|40|05}} [[Declination|Dec]] {{Dec|-69|45|51}}, and is a high-mass X-ray binary (star system) source ([[HMXB]]).<ref name="Rapley">{{Cite journal |last1=Rapley |first1=C. G. |last2=Tuohy |first2=I. R. |date=August 1974 |title=X-Ray Observations of the Large Magellanic Cloud by the Copernicus Satellite |journal=[[The Astrophysical Journal]] |language=en |volume=191 |page=L113 |bibcode=1974ApJ...191L.113R |doi=10.1086/181564 |issn=0004-637X |doi-access=free}}</ref> Of the first five luminous LMC X-ray binaries: LMC X-1, X-2, X-3, X-4 and A 0538–66 (detected by [[Ariel 5]] at A 0538–66), [[Large Magellanic Cloud X-2|LMC X-2]] is the one that is a bright low-mass X-ray binary system ([[LMXB]]) in the LMC.<ref name=Bonnet>{{cite journal |title=LMC X-2: an extragalactic bulge-type source |journal=Astronomy and Astrophysics |date=Apr 1989 |volume=213 |issue=1–2 |pages=97–106 |bibcode=1989A&A...213...97B |last1=Bonnet-Bidaud |first1=J. M. |last2=Motch |first2=C. |last3=Beuermann |first3=K. |last4=Pakull |first4=M. |last5=Parmar |first5=A. N. |last6=Van Der Klis |first6=M. }}</ref>

DEM L316 in the Cloud consists of two supernova remnants.<ref name=Williams>{{cite journal |title=Supernova Remnants in the Magellanic Clouds. VI. The DEM L316 Supernova Remnants |journal=The Astrophysical Journal |date=Dec 2005 |volume=635 |issue=2 |pages=1077–86 |doi=10.1086/497681 |bibcode=2005ApJ...635.1077W|arxiv = astro-ph/0509696 |last1=Williams |first1=R. M |last2=Chu |first2=Y.-H |s2cid=17863461 }}</ref> [[Chandra X-ray Observatory|Chandra]] X-ray spectra show that the hot gas shell on the upper left has an abundance of iron. This implies that the upper-left [[Supernova remnant|SNR]] is the product of a [[Type Ia supernova]]; much lower such abundance in the lower remnant belies a [[Type II supernova]].<ref name="Williams"/>

A 16 ms X-ray pulsar is associated with SNR 0538-69.1.<ref name="MarshallGotthelf1998">{{cite journal|last1=Marshall|first1=F. E.|last2=Gotthelf|first2=E. V|last3=Zhang|first3=W.|last4=Middleditch|first4=J.|last5=Wang|first5=Q. D.|title=Discovery of an Ultrafast X-Ray Pulsar in the Supernova Remnant N157B|journal=The Astrophysical Journal|volume=499|issue=2|date=1998|pages=L179–L182|issn=0004-637X|doi=10.1086/311381|arxiv = astro-ph/9803214 |bibcode = 1998ApJ...499L.179M |s2cid=15812971}}</ref> SNR 0540-697 was resolved using [[ROSAT]].<ref name="ChuKennicutt1997">{{cite journal|last1=Chu|first1=Y.-H.|last2=Kennicutt|first2=R. C.|last3=Snowden|first3=S. L.|last4=Smith|first4=R. C.|last5=Williams|first5=R. M.|last6=Bomans|first6=D. J.|title=Uncovering a Supernova Remnant Hidden Near LMCX-1|journal=Publications of the Astronomical Society of the Pacific|volume=109|date=1997|page=554|issn=0004-6280|doi=10.1086/133913|bibcode = 1997PASP..109..554C |doi-access=free}}</ref>
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