The probe blasted off on its cosmic mission 16 days before its twin, Voyager 1, to account for specific orbital path needs. Every year, an average of four watts of power is lost as the plutonium supplies of each spacecraft continue to deplete. Over the last several years, several science instruments on each of the spacecraft have been disabled to help preserve power. According to NASA, the recent “Big Bang” operation helped prevent the shutdown of another instrument on Voyager 2 before the end of the year. During their missions, both Voyager spacecraft visited Jupiter and Saturn, and Voyager II also flew by Uranus and Neptune.