Chernobyl black frogs reveal evolution in action

The accident at reactor four of the Chernobyl Nuclear Power Plant in 1986 generated the largest release of radioactive material into the environment in human history. The impact of the acute exposure to high doses of radiation ...

Swarm probes weakening of Earth's magnetic field

In an area stretching from Africa to South America, Earth's magnetic field is gradually weakening. This strange behaviour has geophysicists puzzled and is causing technical disturbances in satellites orbiting Earth. Scientists ...

Better energy harvesting with 'law-breaking' device

If you take an object and set it out in the sun, it will begin to warm up. This is because it is absorbing energy from the sun's rays and converting that energy to heat. If you leave that object outside, it will continue ...

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In physics, radiation describes any process in which energy emitted by one body travels through a medium or through space, ultimately to be absorbed by another body. Non-physicists often associate the word with ionizing radiation (e.g., as occurring in nuclear weapons, nuclear reactors, and radioactive substances), but it can also refer to electromagnetic radiation (i.e., radio waves, infrared light, visible light, ultraviolet light, and X-rays) which can also be ionizing radiation, to acoustic radiation, or to other more obscure processes. What makes it radiation is that the energy radiates (i.e., it travels outward in straight lines in all directions) from the source. This geometry naturally leads to a system of measurements and physical units that are equally applicable to all types of radiation.

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