The last time we detected a plasma oscillation was nine years ago.
Gurnett knew that he could use the vibrations in the plasma to determine its density.
When the frequency goes up, it means the density of the plasma is increasing.
1712, "form, shape" (earlier plasm), from Late Latin plasma, from Greek plasma "something molded or created," hence "image, figure; counterfeit, forgery; formed style, affectation," from plassein "to mold," originally "to spread thin," from PIE *plath-yein, from root *pele- (2) "flat, to spread" (see plane (n.1)). Sense of "liquid part of blood" is from 1845; that of "ionized gas" is 1928.
plasma plas·ma (plāz'mə) or plasm (plāz'əm)
The clear, yellowish fluid portion of blood, lymph, or intramuscular fluid in which cells are suspended.
Cell-free, sterilized blood plasma, used in transfusions.
Protoplasm or cytoplasm.
Note: Plasmas are usually associated with very high temperatures — most of the sun is a plasma, for example.