Gravity

physics · force · space

Pulls everything down. Gravity is a force that attracts all objects toward each other. On Earth, it pulls you toward the ground, which is why when you jump, you always come back down.

Keeps planets moving. Gravity from the sun is so strong that it holds all the planets in orbit around it. Without gravity, Earth would fly off into empty space instead of circling the sun.

Controls the tides. The moon's gravity pulls on Earth's oceans and creates tides. When the moon is close to your part of Earth, the ocean bulges toward it, making the water rise and fall every day.

Universal force. Every single object in the universe attracts every other object through gravity, even you and a nearby apple. The force is tiny between small things, but it becomes huge when objects are massive like planets and stars.

Weakens with distance. The farther away two objects are from each other, the weaker gravity's pull becomes. This is why astronauts need rockets to escape Earth's gravity and travel to space.