image: IBEX will improve researchers' understanding of how the heliosphere helps protect us from dangerous galactic cosmic radiation, which originates outside the solar system. This plot illustrates the attenuation of radiation as a function of distance from the Sun or Earth, in the inner solar system. The fraction of the radiation (10 million electron volts) that passes through the inner heliosheath and penetrates into the inner solar system is only about 10 percent of the total radiation in the surrounding galaxy. view more
Credit: Southwest Research Institute