UV rays, or ultraviolet radiation, are produced in two primary ways: naturally by the sun and artificially through electrical processes.
1. Natural Production: The Sun
The sun's immense heat generates UV radiation through a process of incandescent temperature. The sun's core is incredibly hot, causing the atoms within to vibrate and emit electromagnetic radiation, including UV rays, as part of its overall electromagnetic spectrum. This natural UV radiation comprises approximately 10% of the sun's total electromagnetic output. [Wikipedia, Britannica]
2. Artificial Production: Electrical Processes
Artificially, UV radiation is created by passing an electric current through a gas, most commonly vaporized mercury. This process excites the gas atoms, causing them to emit UV light. This method is widely used in various applications, including:
- UV lamps: These lamps are used for sterilization, curing inks and resins, and in some tanning beds. [Live Science, FDA]
- Electric arcs: These produce UV radiation as a byproduct. [Wikipedia]
The specific wavelengths of UV radiation produced depend on the gas used and the intensity of the electrical current. For instance, some UVC lamps may emit small amounts of UVB radiation. [FDA] The interaction of high-energy photons with atmospheric gases also plays a role in the scattering and absorption of UV radiation. [NASA]
In summary, UV radiation's origin lies either in the extreme heat of celestial bodies like the sun or in the controlled excitation of gases via electrical currents in man-made devices. Both natural and artificial sources produce UV radiation, although with varying intensities and wavelength distributions.
