* Have greater mass. The more massive the objects, the stronger the gravitational attraction between them.
* Are closer together. The closer the objects, the stronger the gravitational pull.
Think of it this way:
* Mass: A giant planet like Jupiter has a stronger gravitational pull than a small asteroid, even if they're the same distance away.
* Distance: You feel a stronger gravitational pull from the Earth when you're standing on its surface than when you're in orbit around it.
The exact relationship between mass, distance, and gravitational force is described by Newton's Law of Universal Gravitation.
