It is a typical physical phenomenon of some substances that have the ability to absorb energy in various forms, and therefore to remit it in the form of electromagnetic radiation.
This phenomenon is used, for example, in lighting tubes that contain a mixture of gases, usually argon and mercury vapors, and an inner lining of luminescent powders. The exciter agent in this case is the electric current that passes through the gas, which restores the absorbed energy in the form of cold light.
The Earth's atmosphere is characterized by a faint night glow called night luminescence or luminescence of the atmosphere, also due to various types of radiation that excite the gas particles that compose it.
Night luminescence is a limiting factor for astronomical observations from the ground, because it creates a veil that prevents the weaker sources from being identified.
Another typical luminescence phenomenon occurs in cometary gases and is the one that, in certain occasions, makes comets very bright and spectacular.
|◄ Previous||Next ►|