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Radiation with sufficiently high energy can ionize atoms; that is to say it can knock electrons off atoms, creating ions. Ionization occurs when an electron is stripped (or "knocked out") from an electron shell of the atom, which leaves the atom with a net positive charge.
This will happen only after an extremely long time because first, some (less than 0.1%) [86] matter will collapse into black holes, which will then evaporate extremely slowly via Hawking radiation. The universe in this scenario will cease to be able to support life much earlier than this, after some 10 14 years or so, when star formation ceases.
The photons present during the decoupling are the same photons seen in the cosmic microwave background (CMB) radiation. c. 10–17 million years: The "Dark Ages" span a period during which the temperature of cosmic microwave background radiation cooled from some 4,000 K (3,730 °C; 6,740 °F) down to about 60 K (−213.2 °C; −351.7 °F).
The recombination epoch began after about 379,000 years, when the electrons and nuclei combined into atoms (mostly hydrogen), which were able to emit radiation. This relic radiation, which continued through space largely unimpeded, is known as the cosmic microwave background. [39]
Once photons decoupled from matter, they traveled freely through the universe without interacting with matter and constitute what is observed today as cosmic microwave background radiation (in that sense, the cosmic background radiation is infrared and some red black-body radiation emitted when the universe was at a temperature of some 3000 K ...
“A moment on the lips, a half life on the hips.” Did a Tri-Cities scientist eat radioactive uranium in the ‘80s to prove that it is harmless?. Maybe, says a recent new fact check by Snopes.com.
Hawking radiation is black body radiation released outside a black hole's event horizon due to quantum effects according to a model developed by Stephen Hawking in 1974. [1] The radiation was not predicted by previous models which assumed that once electromagnetic radiation is inside the event horizon, it cannot escape.
In the 19th century, experimenters began to detect unexpected forms of radiation: Wilhelm Röntgen caused a sensation with his discovery of X-rays in 1895; in 1896 Henri Becquerel discovered that certain kinds of matter emit radiation on their own accord.