Portal:Radiation astronomy/Resource/17

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Gamma rays[edit | edit source]

The Moon is seen by the Compton Gamma Ray Observatory, in gamma rays of greater than 20 MeV. Credit: D. J. Thompson, D. L. Bertsch (NASA/GSFC), D. J. Morris (UNH), R. Mukherjee (NASA/GSFC/USRA).

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).

For gamma-ray astronomy, the Vela satellites were the first devices ever to detect cosmic gamma ray bursts.

Gamma-ray bursts (GRBs) are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the most luminous electromagnetic events known to occur in the universe. Bursts can last from ten milliseconds to several minutes, although a typical burst lasts 20–40 seconds. The initial burst is usually followed by a longer-lived "afterglow" emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).[1]

References[edit | edit source]