Title: Nuclear Electromagnetic Pulse: How It Works and When to Worry About It
Headings: Nuclear bombs trigger a strange effect that can fry your electronics — here's how it works
Nuclear bombs trigger a strange effect that can fry your electronics — here's how it works
An illustration of electromagnetic radiation.
How electromagnetic pulse works
A nuclear test blast.
Why altitude is everything
An illustration of a nuclear blast in a city.

Content: Shutterstock
Nuclear blasts trigger an effect called electromagnetic pulse, or EMP. EMP can disrupt or even destroy electronics from miles away. Blasts miles above a country like the US might severely damage its electric and telecommunications infrastructure. A nuclear detonation creates plenty of terrifying effects, including a blinding (and burning) flash of light, a building-toppling blast wave, an incendiary fireball, and radioactive fallout that can drift for hundreds of miles. But there's a lesser-known consequence of a nuclear explosion that can drastically expand its damage zone: an electromagnetic pulse, or EMP. EMPs are rapid, invisible bursts of electromagnetic energy. They occur in nature, most frequently during lightning strikes, and can disrupt or destroy nearby electronics. However, nuclear EMPs — if a detonation is large enough and high enough — can cover an entire continent and cripple tiny circuits inside modern electronics on a massive scale, according to US government reports. The power grid, phone and internet lines, and other infrastructure that uses metal may also be prone to the effects, which resemble those of a devastating geomagnetic storm.