An electromagnetic pulse, or EMP, bomb is a bomb that’s designed to go above the atmosphere and release huge amounts of energy. In less than a billionth of a second, the electrical intensity on Earth’s surface would become so hot that microchips would fry, power lines would overload and the electric grid would collapse.
Everything with microelectronics in it would stop: your car, your computer, the subway. There would be no electricity.
* Some of the energy emitted by an EMP bomb is in the form of gamma rays. Gamma rays are essentially X-rays that have much greater energy — a million volts of energy.
* When the gamma rays hit the atmosphere, they bump into nitrogen and oxygen molecules, knocking off electrons and creating electric current in space. As this current moves through the Earth’s magnetic field, it emits microwaves that strike the surface with an intense and instantaneous surge of power.
* Auroras are caused when electrons carried by solar winds are trapped in the Earth’s magnetic field. The most common color in an aurora is green, but you are likely to find red and purple hues in auroras located higher up in the sky.
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