Gravitational describes anything related to gravity, the invisible force that pulls objects toward each other. When scientists talk about Earth's gravitational pull, they mean the force that keeps your feet on the ground and makes dropped objects fall downward. The moon's gravitational influence helps cause ocean tides by pulling on Earth's water.

Isaac Newton discovered that all objects with mass create a gravitational force. The more massive something is, the stronger its gravitational attraction. Earth's gravitational pull is strong enough to help hold the moon in orbit, while the sun's massive gravitational force keeps the planets circling around it. Even you have a tiny gravitational pull, though it's far too weak to notice.

You might hear about gravitational fields, which describe the area around an object where its gravity affects other things, or gravitational waves, ripples in space itself caused by massive cosmic events like colliding black holes. When astronauts experience zero gravity in space, they're actually still within Earth's gravitational field, but they're falling toward Earth at the same rate as their spacecraft, creating the feeling of weightlessness.