Escape velocity facts for kids

Escape velocity is the special speed an object needs to completely break free from the gravity of a large body, like a planet or a star. Imagine throwing a ball upwards from Earth. It goes up, slows down, and then falls back because of Earth's gravity. But what if you could throw it so fast that it never fell back? Instead, it would keep going into space, moving farther and farther away from Earth. That minimum speed is called escape velocity.

For Earth, the escape velocity at its surface is about 11.2 kilometers per second. That's roughly 6.96 miles per second! This speed is needed if there's no air resistance slowing the object down.

This speed is incredibly fast. Even a bullet shot into the sky will fall back down. A bullet's speed is usually less than 1 kilometer per second, which is far from the escape velocity needed to leave Earth.

Spacecraft starting from Earth's surface begin with no speed. But they have powerful engines and enough fuel. These engines can keep pushing the spacecraft, making it go faster and faster. Once it reaches escape velocity, the engine can even be turned off. The spacecraft will then continue its journey into space on its own.

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  Luna 1, launched in 1959, was the first object made by humans to reach escape velocity from Earth.

See also

In Spanish: Velocidad de escape para niños