background radiation Radiation that is normally present in an environment. Such radiation must be taken into account when measuring radiation from a particular source. On Earth, background radiation is caused by the decay of naturally radioactive substances in surface rocks. In space, the so-called cosmic microwave background is attributed to the Big Bang. Related category • ATOMIC AND NUCLEAR PHYSICS Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |