It depends. Around earth, there are cosmic ray collisions are about 100 per m^2 per year for energies > 1e15eV, and 1 per km^2 per century for > 1e20eV. Most of the very high energy particles are extrasolar in nature. The sun accelerates particles during sunspots to the lower GeV range (around 1e12). Rarely ever do they exceed 10GeV (1e13). Particle acceleration by the sun is generally accepted to be due to a process known as "reconnection"
For comparison,CERN is working on the Large Hadron Collider (LHC), an accelerator due to activate in 2007 that will reach energies of 1.15e15 TeV by smashing lead nuclei together.
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"Illuminant light,
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