Radiation: the process in which energy is emitted as particles or waves, the complete process in which energy is emitted by one body, transmitted through an intervening medium or space, and absorbed by another body, energy is transferred to other mass-energy by these processes.
Electromagnetic radiation is perceived as light by our senses. Photons, are particles of light which resonate as a beam of light to our senses. They have a wavelengths of 400-700 nanometers (a tiny wavelength) that our eye can see.
The color Red has the lowest energy and the longest wavelength.
Violet has the shortest wavelength and the highest energy.
In order from lowest energy and longest wavelength to the shortest wavelength and the highest energy, like the colors of a rainbow;
ROY G BIV is an easy pneumonic. (Red, Orange, Yellow; Green; Blue, Indigo, Violet)
Long Wavelength = Lower Energy
Shorter Wavelenght = Higher Energy
Radiation varies in wavelength from huge mile long waves, Radio waves can be a thousands feet long and pass through physical matter with little or no effect. As wave-lengths get smaller, the energy that they transmit to other energy increases.
Slightly longer wave-lengths allow our cell phones to work, followed by microwaves, radar and infrared waves. Infrared wave-lengths are about 0.001 to 0.0000001 meter long, or about 1 mm to 0.0001mm long).
Humans perceive color, or Visible Light in the hundreds of nanometer range, which is a very small part of the Electromagnetic Spectrum of radiation (energy transmission in the form of waves).
Ultraviolet radiation, has a wavelength of about 10 to 1000 times shorter than visible light and causes us our skin to burn, tan and for vitamin D to be converted to its active form in though the outer layers of capillaries in out skin. Vitamin D is essential in bone growth and maintenance of our endoskeleton. In latitudes with lower levels of sunlight exposure, lower levels of Vitamin D-3, have been implicated in higher incidences of Multiple Sclerosis and other diseases.
Ultraviolet light is the starting point for ionizing radiation.
Electromagnetic radiation that ionizes, these waves carry enough energy to liberate electrons from atoms and molecules. This radiation has higher energies and can be destructive to life, from sunburns to damaging DNA and cancer. In medicine it can also be used to treat and diagnose various diseases.
X-Rays have a shorter wavelength and a higher energy than Ultraviolet radiation and can diagnose, treat and cause various diseases.
Gamma rays have a very short wavelength and can have ultra-high energies that can even vaporize matter.
Cosmic Rays are emitted by extremely highly energy systems that lie outside our Solar System, like Quasars, Active Galactic Nuclei (Like the Super Massive Blackhole in the center of Spiral Galaxies such as our own Milky Way and from Supernova that will eventually become Neutron Stars or Blackholes)
Classic Radiation that we most associate with “Radiation”, is emitted from elements with lager mass that tend to be unstable, such as Uranium and Plutonium. They release α and β particles that are massive and cannot readily penetrate human tissues but are harmful when internally ingested or otherwise enter the body. Gamma radiation is also released from radioactive elements and can penetrate human tissue through the skin.
Link to a published paper I co-authored linking MS to Vitamin D deficiency and Latitudes.