The Sun's outer layers form the corona, and are heated to millions of degrees by a continual input of energy from the surface, where magnetic fields twist and reconnect. In a hail of millions of solar micro-flares per day, magnetic energy from these constant 'short circuits' is pumped into accelerating protons and electrons to high energy, and these then diffuse into the corona to heat it. The solar wind consists of the flow of particles from the Sun at speeds of 300-400 kilometers/sec. By the time this wind reaches the orbit of the Earth, its density is only about 5 particles (mostly hydrogen and helium nuclei) per cubic centimeter. The Sun loses about 1/100 trillionth of its mass ' every year from this wind- Other stars have much heftier winds that cause the star to lose 1/100,000 of its mass each year.
High-speed wind streams arise from coronal holes. These
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