Skip to Main Content

KS3 Science - Electromagnetic Spectrum: Gamma

A guide to resources on electromagnetic waves, from radio to gamma - their use, danger and occurrence, compiled by your librarians.


French physicist  Henri Becquerel is credited  with discovering gamma radiation

Gamma rays originate in the nucleus. X-rays originate in the electron fields surrounding the nucleus or are machine-produced.

Gamma Rays Information Video

Risks & Dangers


Exposure to X-rays and gamma rays, even at low-dose levels, increases risk of cancer - says a five-year study by a National Research Council committee. 

X-Rays, gamma rays and other radiation emitted from lightning are the subject of study of researchers with concerns about the potential for airline passengers and crews to be exposed to harmful levels of radiation. more....


Sweetsearch a handy web search tool...


(source:NASA website) (Gamma ray astronomy photo)

  • Gamma radiation is very high-energy ionizing radiation, with  about 10,000 times the energy as the photons in the visible spectrum.
  • Gamma photons have no mass and no electrical charge--they are pure electromagnetic energy.
  • Their wave lengths range from 3/100ths to 3/1,000ths of a nanometer.
  • Gamma rays are beyond X-rays on the electromagnetic spectrum. 

Radiation Source

  • Gamma rays can cover hundreds to thousands of meters in air before spending their energy.
  • Gamma radiation can pass through different kinds of materials, including human tissue. Dense material like lead, are commonly used as shielding to slow or stop gamma photons.
  • Gamma rays are spontaneous radiation when certain elements like radium, uranium, and cobalt 60 decompose, or decay. 


Gamma rays are applied to

  • Sterilize surgical equipment, kill harmful bacteria in food - Radiation can modify DNA structure and stop harmful organisms from multiplying
  • Treat nonstick cookware to keep food from sticking to the metal surface.
  • Plant seeds exposed to radiation can bring about new and better types of plants
  • Kill cancer cells - incorrect doses can however cause cancer

More reading....