On average, people in the U.S.A. are exposed to about 3.6 milliSieverts of radiation each year. Click on image for full size (57K JPEG) Windows to the Universe original artwork using data from the National Council on Radiation Protection and Measurements.

Radiation comes in two basic types: electromagnetic radiation transmitted by photons, and particle radiation consisting of electrons, protons, alpha particles, and so forth.

Electromagnetic radiation, transmitted as photons, includes everything from relatively benign radio waves to dangerous and powerful X-rays and gamma rays. Energy levels across the electromagnetic spectrum vary 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.

On average, people in the U.S.A. are exposed to about 3.6 milliSieverts of radiation each year. Click on image for full size (57K JPEG) Windows to the Universe original artwork using data from the National Council on Radiation Protection and Measurements.

Radiation comes in two basic types: electromagnetic radiation transmitted by photons, and particle radiation consisting of electrons, protons, alpha particles, and so forth.

Electromagnetic radiation, transmitted as photons, includes everything from relatively benign radio waves to dangerous and powerful X-rays and gamma rays. Energy levels across the electromagnetic spectrum vary 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.

On average, people in the U.S.A. are exposed to about 3.6 milliSieverts of radiation each year. Click on image for full size (57K JPEG) Windows to the Universe original artwork using data from the National Council on Radiation Protection and Measurements.

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