My Way News - NASA to launch probe to map solar system's edge
AP reports: "The solar wind, a stream of charged particles spewing from the sun at 1 million miles per hour, carves out a protective bubble around the solar system. This bubble known as the heliosphere shields against most dangerous cosmic radiation that would otherwise interfere with human spaceflight. Scientists recently discovered that the solar wind pressure is at its weakest level in 50 years, although the exact reason remains a mystery."