What's a gravity assist? | Mashable?

A gravity assist is like getting a free push from a friend when you're playing tag, it helps you go faster or change direction without using extra energy.

Imagine you’re on a skateboard, zooming past your friend who’s standing still. When you pass them, they give you a quick kick to make you go even faster. That's kind of what happens with a gravity assist.

When a spaceship is flying by a planet, the planet acts like that friendly tag player, it gives the spaceship a little nudge. If the spaceship passes close enough to the planet, it can pick up more speed or change direction completely. This helps the spaceship save fuel and go farther without needing extra power.

Think of it like this: you’re riding your bike down a hill, and you jump on a moving merry-go-round, you get an extra boost and keep going faster than before!

When the Voyager spacecraft flew by Jupiter, it used a gravity assist to speed up so much that it could reach Saturn and beyond, all with less fuel than if it had just kept going straight.