How does gamma radiation work

National Aeronautics and Space Administration. Brighter colors in the Cygus region indicate greater numbers of gamma rays detected by the Fermi gamma-ray space telescope. Krause et al. Electromagnetic Spectrum Series Series Homepage. Infrared Waves. Reflected Near-Infrared. Visible Light. Ultraviolet Waves. Earth's Radiation Budget. Diagram of the Electromagnetic Spectrum. Recommended Articles. September 24, Ionizing radiation has so much energy it can knock electrons out of atoms, a process known as ionization.

Ionizing radiation can affect the atoms in living things, so it poses a health risk by damaging tissue and DNA in genes. Ionizing radiation comes from x-ray machines, cosmic particles from outer space and radioactive elements. Radioactive elements emit ionizing radiation as their atoms undergo radioactive decay. Radioactive decay is the emission of energy in the form of ionizing radiation ionizing radiation Radiation with so much energy it can knock electrons out of atoms.

The ionizing radiation that is emitted can include alpha particles alpha particles A form of particulate ionizing radiation made up of two neutrons and two protons. Alpha particles pose no direct or external radiation threat; however, they can pose a serious health threat if ingested or inhaled. Some beta particles are capable of penetrating the skin and causing damage such as skin burns. Beta-emitters are most hazardous when they are inhaled or swallowed.

Gamma rays can pass completely through the human body; as they pass through, they can cause damage to tissue and DNA. Radioactive decay occurs in unstable atoms called radionuclides. The energy of the radiation shown on the spectrum below increases from left to right as the frequency rises. Other agencies regulate the non-ionizing radiation that is emitted by electrical devices such as radio transmitters or cell phones See: Radiation Resources Outside of EPA. Alpha particles come from the decay of the heaviest radioactive elements, such as uranium , radium and polonium.

Even though alpha particles are very energetic, they are so heavy that they use up their energy over short distances and are unable to travel very far from the atom. The health effect from exposure to alpha particles depends greatly on how a person is exposed. Alpha particles lack the energy to penetrate even the outer layer of skin, so exposure to the outside of the body is not a major concern.

Gamma rays can be used to treat cancer, and gamma-ray bursts are studied by astronomers. Electromagnetic EM radiation is transmitted in waves or particles at different wavelengths and frequencies. This broad range of wavelengths is known as the electromagnetic spectrum.

The spectrum is generally divided into seven regions in order of decreasing wavelength and increasing energy and frequency. The common designations are radio waves, microwaves, infrared IR , visible light, ultraviolet UV , X-rays and gamma rays. Gamma rays fall in the range of the EM spectrum above soft X-rays. A picometer is one-trillionth of a meter. Gamma rays and hard X-rays overlap in the EM spectrum, which can make it hard to differentiate them.

In some fields, such as astrophysics, an arbitrary line is drawn in the spectrum where rays above a certain wavelength are classified as X-rays and rays with shorter wavelengths are classified as gamma-rays.

Both gamma rays and X-rays have enough energy to cause damage to living tissue, but almost all cosmic gamma rays are blocked by Earth's atmosphere. A few years later, New Zealand-born chemist and physicist Ernest Rutherford proposed the name "gamma rays," following the order of alpha rays and beta rays — names given to other particles that are created during a nuclear reaction — and the name stuck.

Gamma-ray astronomy did not develop until it was possible to get our detectors above all or most of the atmosphere, using balloons or spacecraft. The first gamma-ray telescope, carried into orbit on the Explorer XI satellite in , picked up fewer than cosmic gamma-ray photons!

Unlike optical light and X-rays, gamma rays cannot be captured and reflected in mirrors. The high-energy photons would pass right through such a device. Gamma-ray telescopes use a process called Compton scattering, where a gamma-ray strikes an electron and loses energy, similar to a cue ball striking an eight ball. This picture was taken from an orbiter window.

What do gamma-rays show us? If you could see gamma-rays, the night sky would look strange and unfamiliar. The gamma-ray moon just looks like a round blob - lunar features are not visible.