Kosmisk stråling

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Kosmiske stråler er subatomare partikler eller atomer med oprindelse udenfor Jordens atmosfære, som har en kinetisk energi fra nogle få milliarder eV til mere end 10²⁰ eV. De subatomare partikler kan være elektroner, protoner, neutroner og ioniserede atomer. De ioniserede atomer er fra en stor del af det periodiske system - helt op til uran.

En lille del, ca. 0,1% af de kosmiske stråler, er fotoner i form af gammastråler.

I 1993 observerede man i Utah den mest energirige kosmiske stråle partikel på 3*10²⁰ eV.

Når jordens atmosfære rammes af en partikel eller gammafotoner vil jordens magnetfelt og atmosfærens gas omdanne og bremse en kosmisk stråle.

Det formodes at hovedkilden til kosmiske stråler er supernovaeksplosioner.

[redigér] Kilder/referencer

• 23 April, 2002, BBC News, Cosmic ray mystery 'solved' Citat: "..."For the first time, we see the hint of a possible connection between the arrival directions of ultra-high energy cosmic rays and locations on the sky of nearby dormant galaxies hosting supermassive black holes," said Princeton's Dr Diego Torres..."
  • 2004-11-05, Sciencedaily: Possible Origin Of Cosmic Rays Revealed With Gamma Rays Citat: "...luckily for life on Earth, gamma rays from objects in outer space are stopped by the atmosphere..."
• 2005-09-23, Sciencedaily: Tycho's Remnant Provides Shocking Evidence For Cosmic Rays Citat: "...some modern ideas of the aftermath of supernova explosions may have to be revised. The report by Hughes and colleagues demonstrates that the shock wave produced by the explosive disruption of the star behaves in a way that cannot be explained by the standard theory..."

[redigér] Se også

• Polarlys (nordlys og sydlys)

[redigér] Eksterne henvisninger

• University of Leeds: What are cosmic rays?
• Google: Cosmic Rays
• Cosmic Rays
• Pierre Auger Observatory: An International Facility to Study the Highest Energy Cosmic Rays
• Northeastern University: Cosmic ray papers
• 31 October, 2003, BBCNews: Solar storm surge 'not over yet' Citat: "...aircraft traversing the north Atlantic were confined to a narrow corridor to minimise radiation exposure..."
• 2004-05-05, Sciencedaily: Scientists Announce Cosmic Ray Theory Breakthrough Citat: "...The theory could be the basis for a whole new understanding of the ways in which cosmic rays -- and their signature radio waves -- propagate and travel through intergalactic space..."