Gravity in Space

What Is Gravity?

Gravity is a force that pulls objects toward each other. On Earth it keeps us on the ground. The bigger an object, the stronger its gravity. The Sun, the Earth, and even tiny rocks all have gravity.

Gravity in Space

In space there is still gravity, but it is weaker than on Earth. The International Space Station circles the Earth about 400 kilometers up. It feels weightless because it is falling around the Earth, not because there is no gravity. The Moon’s gravity is only one‑sixth of Earth’s, so astronauts can jump higher there. Planets far from the Sun feel less pull from the Sun, while planets close to it feel more.

Why It Matters

Gravity decides how planets stay in orbit. It makes moons circle planets and keeps the Sun at the center of the solar system. Without gravity, space would be a chaotic mess of drifting rocks. Understanding gravity helps scientists send rockets to the right place and keeps astronauts safe.