Gamma-ray astronomy is the astronomical study of the cosmos with gamma rays. Gamma-rays are the most energetic form of "light" (electromagnetic radiation) that travel across the universe, and gamma-rays thus have the smallest wavelength of any wave in the electromagnetic spectrum.
Gamma-rays are created by celestial events such as supernova explosions, destruction of positrons, creation of black holes and even the decay of radioactive material (gamma decay) in space. For example, supernova SN 1987A emitted an "afterglow" of gamma-ray photons from the decay of newly-made radioactive cobalt-56 ejected into space in a cloud, by the explosion. Most astronomical gamma-rays are thought to be produced not from radioactive decay, however, but from the same type of accelerations of electrons, and electron-photon interactions, that produce X-rays in astronomy (but occurring at a higher energy in the production of gamma-rays). Astronomical literature tends to hyphenate "gamma-ray" by analogy with the term "X-ray."
Read more about Gamma-ray Astronomy: Early History, Gamma-ray Discoveries, Balloon Flights, Solar Flares, Recent and Current Observatories, Focusing Gamma-rays
Other articles related to "astronomy":
... Gamma ray astronomy is the study of astronomical objects at the shortest wavelengths of the electromagnetic spectrum ... Most gamma-ray emitting sources are actually gamma-ray bursts, objects which only produce gamma radiation for a few milliseconds to thousands of ... Only 10% of gamma-ray sources are non-transient sources ...
... Early experimenters in X-ray and gamma-ray astronomy found that their detectors, flown on balloons or sounding rockets, were corrupted by the large fluxes of high-energy photon ... Gamma-rays, in particular, could be collimated by surrounding the detectors with heavy shielding materials made of lead or other such elements, but it was quickly discovered that the high fluxes ... ("BGO"), or other active shielding materials are used to detect and veto gamma-ray events of non-cosmic origin ...
... A discovery in 2012 may allow focusing gamma-ray telescopes ... At photon energies greater than 700 keV, the index of refraction starts to increase again ...
Famous quotes containing the word astronomy:
“It is noticed, that the consideration of the great periods and spaces of astronomy induces a dignity of mind, and an indifference to death.”
—Ralph Waldo Emerson (1803–1882)