A coronal mass ejection (CME) is a massive burst of solar wind, other light isotope plasma, and magnetic fields rising above the solar corona or being released into space.
Coronal mass ejections release huge quantities of matter, magnetic
fields and electromagnetic radiation into space above the sun's
surface, either near the corona or farther into the planet system or
beyond (interplanetary CME). The ejected material is a plasma consisting primarily of electrons and protons, but may contain small quantities of heavier elements such as helium, oxygen, and even iron. It is associated with enormous changes and disturbances in the coronal magnetic field.