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The Van Allen radiation belt is a torus of energetic charged particles (plasma) around Earth, which is held in place by Earth's magnetic field. This field is not uniformly distributed around the Earth. On the sunward side, it is compressed because of the solar wind, while on the other side it is elongated to around three earth radii. This creates a cavity called the Chapman Ferraro Cavity, in which the Van Allen radiation belt resides. It is split into two distinct belts, with energetic electrons forming the outer belt and a combination of protons and electrons creating the inner belt. In addition, the belts contain lesser amounts of other nuclei, such as alpha particles. The Van Allen belts are closely related to the polar aurora where particles strike the upper atmosphere and fluoresce. Prior to the Space Age, the possibility of trapped charged particles had been investigated by Kristian Birkeland, Carl Størmer, and Nicholas Christofilos. The existence of the belt was confirmed by the Explorer 1 and Explorer 3 missions in early 1958, under Dr James Van Allen at the University of Iowa. The trapped radiation was first mapped out by Explorer 4, Pioneer 3 and Luna 1. The term Van Allen belts refers specifically to the radiation belts surrounding Earth; however, similar radiation belts have been discovered around other planets. The Sun does not support long-term radiation belts. The Earth's atmosphere limits the belts' particles to regions above 200–1,000 km, while the belts do not extend past 7 Earth radii RE. The belts are confined to an area which extends about 65° from the celestial equator. An upcoming NASA mission, Radiation Belt Storm Probes, will go further and gain scientific understanding (to the point of predictability) of how populations of relativistic electrons and ions in space form or change in response to changes in solar activity and the solar wind. From Wikipedia under the
GNU Free Documentation License What will happen to the Van Allen radiation belt in the year 2012? Q. Will the Van Allen radiation belt collapse and reform in its original form. In 1962 an attempt was made to atomically blast a passage through the belt, for space vehicles to travel through forming a third belt, will the third belt still remain? Asked by bruce451us - Tue Sep 25 16:24:09 2007 - - 5 Answers - 0 Comments A. who knows...does it matter? and its not Mayan garbage. its not even a calander either. calanders are for the moons...this one is for the sun. and it was the Aztecs...but they called themselves Mexica. and it states that a new phase starts in December 23 of 2012, not that the world is gonna end. get it right! Answered by Ghost - Wed Sep 26 00:54:07 2007 what do the van allen belts hold?why does this happen? Q. what do the van allen belts hold?why does this happen? Asked by kf8890 - Mon Feb 13 14:32:04 2006 - - 2 Answers - 0 Comments A. The Van Allen radiation belts were discoverred with the first rockets that actually got that far into outer space by von Braun and Van Allen. There are actually three seperate layers. However, since I prefer to answer only from my personal knowledge, and not look things up, I can't tell you the names of the three different layers, although I suppose someone else will name them further on. They serve as a sink for cosmic radiation and prevent it from getting to the surface of the earth. This is a good thing as it allows life to propagate on the planet. I guess some might consider it a 'bad thing' as such. Answered by bred2bbroken - Mon Feb 13 14:37:26 2006 space travel outside of the Van Allen Belt?
Q. When men flew to the moon outside of the protective radiation shield surrounding Earth (Van Allen Belt) why didn't radiation kill the spacemen as their space-suits would have had to be made of thick lead to stop the radiation damage. Also, with this radiation in mind ,how was it possible to take photos on the moon as the radiation would have damaged (fogged)the film Asked by SUNNY - Mon Aug 13 12:40:50 2007 - - 6 Answers - 0 Comments A. Where do you get your information about radiation? Wherever it is, I strongly urge you to ditch that source and read a real textbook on the subject. The van Allen radiation belts are zones of energetic charged particles (mostly protons and electrons) trapped by Earth's magnetic field. Lead is a terrible shield against particle radiation because of a phenomenon called bremmstrahlung. Put simply, the absorption by the lead of an energetic charged particle causes the subsequent emission of an x-ray. Your shield actually generates radiation, and more penetrating radiation than it was supposed to shield against! You need light metals such as aluminium, plastics, or water to shield against particle radiation, and the shield doesn't have to be… [cont.] Answered by Jason T - Mon Aug 13 18:18:02 2007 From Yahoo Answer Search: "Van Allen belts"  news.google.com Inside Pulse (blog) Mark Allen : Mystery opponent is Jeff Hardy and he soundly defeats Red to win the belt . Steven Gepp: The matches in this feud have disappointed me a little. ... and more » news.google.com The Decatur Daily We will have extra personnel on the road to make sure motorists are wearing their seat belts and driving safely, Johnson said. ... and more » news.google.com De Telegraaf En als je dan de politie belt heeft het geen prioriteit (boven een bak koffie of thee?).Hoe kan het toch dat we in een neerwaartse spiraal van normen en ... and more » From Google News Search: "Van Allen belts"  astronomygcse.co.uk 386px x 541px | 17.10kB [source page] come from the Sun They now bounce back and forth from pole to pole in two belts as shown below The outer belt extending to about 24 000 km The belts are actually doughnut shaped The charged particles are dangerous to astronauts fast moving electrons are beta radiation However astronauts are exposed to a huge amount of radiation anyway when they go into space  universetoday.com 397px x 531px | 35.00kB [source page] and Aurora Australis respectively However some particles are fed into the magnetosphere and become trapped between the onion skin like layers of magnetic field lines and cannot escape This is how the Van Allen Belts are supplied and the population of protons and electrons are expected to increase and become more energetic during solar storms Although we know a lot about From Yahoo Image Search: "Van Allen belts"  spacestation-shuttle.blogspot.com SHELDON KALNITSKY - NASA International Space Station Mission Shuttle Google Earth Science News Technology Mars Solar System Universe Astronomy Moon Milky Way Planet Earth Satellite Telescope Wed, 27 Jan 2010 12:44:00 GM The name honors the launch and scientific discoveries of the Explorer-1 mission, which detected the . Van Allen. radiation . belts. more than 50 years ago. E1P will carry a miniature Geiger tube to measure the intensity and variability of the ...  bautforum.com Hungry4info Fri, 04 Sep 2009 13:35:05 GM i recently got into a debate with someone over the internet about the . van allen belts. . he wants me to show him several items, none of which i have, or have been able to find yet. -> proton/electron flux in the inner . belt. . ...  fff900.blogspot.com Novi Irawan Mon, 25 Jan 2010 14:24:00 GM Some images indicate that the Astronauts appeared to be in spotlight; The . Van Allen. Radiation . Belt. - Could the Astronauts survive travelling through the deadly radiation . belt. which is situated 500 miles above the earth and is 1000's of ... From Google Blog Search: "Van Allen belts" |
