Extragalactic cosmic ray Extragalactic cosmic ray Extragalactic cosmic rays are very-high-energy particles that flow into the Solar System from beyond the Milky Way galaxy. The energies these particles possess are in excess of 10 eV. Unlike solar or galactic cosmic rays, little is known about the origins of extragalactic cosmic rays. This is largely due to a lack of statistics: only about 1 extragalactic cosmic ray particle per square meter per year reaches the Earth's surface (see figure). There are many ideas about which processes may be responsible for cosmic rays with such high energies. In the 'bottom-up' approach, cosmic rays gain more
Mountains Beyond Mountains Health Organization, and largely supported financially by an American benefactor, Tom White. PART IV: A Light Month for Travel Follows Farmer from Haiti to Cuba, Paris, Russia, and other locations in his quest to treat infectious disease. PART V: O for the P In 2000, PIH learns it has been awarded a $45 million grant, by the Bill & Melinda Gates Foundation, to combat MDR-TB in Lima, Peru, along with other organizations. "O for the P" refers to an expression within PIH that is a shortened form of saying “a preferential option for the poor”. Mountains Beyond Mountains Mountains Beyond