Solar phenomena move about and can travel at a few hundred meters per second when they first appear. The solar wind is a stream of plasma released from the Sun's upper atmosphere. It consists of mostly electrons and protons with energies usually between 1.5 and 10 keV. The stream of particles varies in density, temperature and speed over time and over solar longitude. These particles can escape the Sun's gravity because of their high energy. The solar wind is divided into the slow solar wind and the fast solar wind. The slow solar wind has a velocity of about , a temperature
Piezoelectric direct discharge plasma than 50 C. At the same time, the electrons and the ions reach energies of 1 – 10 eV. This is 300 – 3000 times higher than the average energy of the neutral gas particles. The densities of the electrons and the ions reach 10 – 10 m. Since most of the plasma volume consists of the cold neutral gas, the plasma is cold. However, the very energetic electrons and ions excite atoms and molecules producing large amounts of short-lived chemical species, making this plasma chemically very active. Properties of the piezoelectric direct discharge plasmas enable a large spectrum of