Editing Cosmic ray (section)

{{short description|High-energy particle, mainly originating outside the Solar System}}
{{Redirect|Cosmic radiation|some other types of cosmic radiation|Cosmic background radiation|and|Cosmic background (disambiguation)|the film|Cosmic Ray (film)}}
{{Use dmy dates|date=September 2019}}
{{Use American English|date=March 2021}}

[[File:Cosmic ray flux versus particle energy.svg|360px|thumb|Cosmic [[flux]] versus particle energy at the top of Earth's atmosphere]]
[[File:Hard-component-muon-868x1024.png|thumb|right|Left image: cosmic ray muon passing through a cloud chamber undergoes scattering by a small angle in the middle metal plate and leaves the chamber. Right image: cosmic ray muon losing considerable energy after passing through the plate as indicated by the increased curvature of the track in a magnetic field.]]

'''Cosmic rays''' or '''astroparticles''' are [[high-energy particle]]s or clusters of particles (primarily represented by [[proton]]s or [[atomic nuclei]]) that move through space at nearly the [[speed of light]]. They originate from the [[Sun]], from outside of the [[Solar System]] in our own galaxy,<ref>
{{cite book|last=Sharma|first=Shatendra|title=Atomic and Nuclear Physics|date=2008|publisher=Pearson Education India|isbn=978-81-317-1924-4|page=478}}
</ref> and from distant galaxies.<ref>{{cite news|title=Detecting cosmic rays from a galaxy far, far away|date=21 September 2017|website=Science Daily|url=https://www.sciencedaily.com/releases/2017/09/170921141257.htm|access-date=26 December 2017}}
</ref> Upon impact with [[Atmosphere of Earth|Earth's atmosphere]], cosmic rays produce [[air shower (physics)|showers of secondary particles]], some of which reach the [[Earth's surface|surface]], although the bulk are [[Deflection (physics)|deflected]] off into space by the [[Earth's magnetic field|magnetosphere]] or the [[heliosphere]].

Cosmic rays were discovered by [[Victor Francis Hess|Victor Hess]] in 1912 in balloon experiments, for which he was awarded the 1936 [[Nobel Prize in Physics]].<ref name=HessNobelPresSp/>

Direct measurement of cosmic rays, especially at lower energies, has been possible since the launch of the first satellites in the late 1950s. Particle detectors similar to those used in nuclear and high-energy physics are used on satellites and space probes for research into cosmic rays.<ref>{{cite book|editor=Cilek, Vaclav|year=2009|title=Earth System: History and Natural Variability|volume=I|page=165|chapter=Cosmic Influences on the Earth|publisher=Eolss Publishers|isbn=978-1-84826-104-4|chapter-url=https://www.eolss.net/ebooklib/bookinfo/earth-system-history-natural-variability.aspx}}
</ref> Data from the [[Fermi Gamma-ray Space Telescope|Fermi Space Telescope]] (2013)<ref name=ackermann-2013>{{cite journal|last1=Ackermann|first1=M.|last2=Ajello|first2=M.|last3=Allafort|first3=A.|last4=Baldini|first4=L.|last5=Ballet|first5=J.|last6=Barbiellini|first6=G.|last7=Baring|first7=M.G.|last8=Bastieri|first8=D.|last9=Bechtol|first9=K.|last10=Bellazzini|first10=R.|last11=Blandford|first11=R.D.|last12=Bloom|first12=E.D.|last13=Bonamente|first13=E.|last14=Borgland|first14=A.W.|last15=Bottacini|first15=E.|last16=Brandt|first16=T.J.|last17=Bregeon|first17=J.|last18=Brigida|first18=M.|last19=Bruel|first19=P.|last20=Buehler|first20=R.|last21=Busetto|first21=G.|last22=Buson|first22=S.|last23=Caliandro|first23=G.A.|last24=Cameron|first24=R.A.|last25=Caraveo|first25=P.A.|author25-link=Patrizia A. Caraveo|last26=Casandjian|first26=J.M.|last27=Cecchi|first27=C.|last28=Celik|first28=O.|last29=Charles|first29=E.|last30=Chaty|first30=S.|display-authors=6|date=15 February 2013|journal=[[Science (journal)|Science]]|volume=339|issue=6424|pages=807–811|title=Detection of the characteristic pion decay-signature in supernova remnants|doi=10.1126/science.1231160|arxiv=1302.3307|bibcode=2013Sci...339..807A|pmid=23413352|s2cid=29815601}}
</ref> have been interpreted as evidence that a significant fraction of primary cosmic rays originate from the [[supernova]] explosions of stars.<ref name=pinholster-2013>{{cite press release|author=Pinholster, Ginger|date=13 February 2013| title=Evidence shows that cosmic rays come from exploding stars|publisher=[[American Association for the Advancement of Science]]|location=Washington, DC|url=http://www.aaas.org/news/releases/2013/0214_supernova_cosmicrays.shtml}}
</ref>{{better source needed|date=September 2023}}<!-- This is a press release. It would be better to directly cite the research it was based on. --> Based on observations of [[neutrino]]s and [[gamma ray]]s from [[blazar]] [[TXS 0506+056]] in 2018, [[active galactic nuclei]] also appear to produce cosmic rays.<ref name="nature">
{{cite journal
 |last1=Abramowski |first1=A.
 |collaboration=HESS Collaboration
 |year=2016
 |title= Acceleration of petaelectronvolt protons in the Galactic Centre
 |journal= [[Nature (journal)|Nature]]
 |volume=531 |issue= 7595 |pages= 476–479
 |doi= 10.1038/nature17147
 |arxiv = 1603.07730 |bibcode= 2016Natur.531..476H
 |pmid= 26982725 |s2cid= 4461199
}}
</ref><ref>{{cite journal|last=Aartsen|first=Mark|collaboration=IceCube Collaboration|date=12 July 2018|title=Neutrino emission from the direction of the blazar TXS 0506+056 prior to the IceCube-170922A alert|journal=Science|volume=361|issue=6398|pages=147–151|doi=10.1126/science.aat2890|issn=0036-8075|pmid=30002248 |bibcode=2018Sci...361..147I|arxiv=1807.08794|s2cid=133261745}}
</ref>