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Cosmic rays are high energy charged particles, originating in outer space that travel nearly the speed of light and strikes the earth from all directions (The Pierre Auger Collaboration, 2007); most of them are nuclei of atoms ranging from lightest to heaviest element in the periodic table. Cosmic rays also include high energy electrons, positrons, and other subatomic particles; billions of cosmic rays slam into the earth every second, most of them with a quite low energy. While they are called cosmic rays, it has been noticed that they are point like particles and not rays. Aside from protons which make up 90% of all cosmic rays, there are also Helium nuclei, also known as alpha particles which make up another 9%, and electrons which make up the remaining 1% (http://imagine.gsfc.nasa.gov/docs/science/know_l1/cosmic_rays.html).
Several studies reveal that outer space is filled with a bath of fast moving particles, known as the cosmic ray flux (Mewaldt et al., 1996; Susan, 1997; Baltrusaitis et al., 2001; Kopenkin, 2002; and Vernon, 2009). Scientists analyze cosmic rays as ionized radiations because they have the tendency to impact molecules with such force that they knock the electrons off their constituent atoms, creating destructive ions. An example of such ionized radiations can be very well understood by a piece of biomaterial which when left unprotected for a long time in the cosmic environment would turn into Swiss cheese. One of the greatest challenges for human space colonization is: how to repel them (Franco and Ewa, 2009).
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