Inside the Iron Dome, the invisible shield protecting Israeli cities
The "iron boom" comes next – the familiar sound of Israel's air defence system in action as interceptor missiles take out rockets in mid-air.
"If you can hear a boom in the air, you can be happy," said Hilla Haddad Chmelnik, an aerospace engineer who played a key role in the Iron Dome's development.
Analysts say if a missile is travelling at 1km per second, there would be – at most – one minute to respond to the attack.
Developed with backing from the United States, it has been described as one of the most effective air defence systems on the planet.
Israel said the Iron Dome intercepted more than 2,400 projectiles in the first decade of operation, saving thousands of lives.
Its Tamir interceptor missiles soar through the air at two times the speed of sound, using steering fins and heat-seeking sensors to come within 10 metres of a target.
The volumes of missiles, drones and rockets hurtling towards the country from Iran and its proxies are larger, more powerful and sophisticated.
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