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After having suspected it for more than ____________________ decade , for ____________________ first time , scientists have found evidence that ____________________ most energetic particles are generated outside ____________________ Milky Way . Those responsible for this discovery have been ____________________ astronomers of ____________________ Pierre Auger Observatory in Argentina , who are very satisfied to have checked ____________________ hypothesis .

Although ____________________ study has not been able to identify the concrete sources of cosmic rays or how they reach such high levels of energy , analyzes performed over ____________________ period of twelve years " have finally revealed that particles with ____________________ upper ranges of energy have ____________________ extragalactic origin , " says Alan Watson , founder astronomer of ____________________ observatory .