On average, people in the U.S.A. are exposed to about 3.6 milliSieverts of radiation each year.
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Windows to the Universe original artwork using data from the National Council on Radiation Protection and Measurements.
Radiation comes in two basic types: electromagnetic
by photons, and particle
radiation consisting of
electrons, protons, alpha particles, and so forth.
transmitted as photons,
includes everything from relatively benign radio
dangerous and powerful X-rays and gamma
Energy levels across the electromagnetic
inversely with wavelength.
Particle radiation involves
fast-moving sub-atomic particles, such as electrons, protons,
and nuclei (ions) of Helium and heavier elements.
Exposure to too much
radiation of various types can be harmful to humans and other living
things. Radiation can also fry the electronics in spacecraft, disabling them.
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