The force that pulls matter towards the center of a celestial body or another object is called gravity. According to the general theory of relativity, gravity is not a force, but instead is a curvature of space-time caused by the presence of mass and energy.

In simpler terms, the more massive an object is, the greater its gravitational pull. This means that objects with a large mass, such as planets and stars, have a stronger gravitational pull than objects with a smaller mass, such as people or cars.

The gravitational force between two objects is directly proportional to the product of their masses, and inversely proportional to the square of the distance between them.

So, the greater the mass of the objects, the stronger the gravitational pull between them. And the farther apart the objects are, the weaker the gravitational pull between them.

Gravitational force plays a crucial role in holding celestial objects together, determining their orbits, and governing many of the phenomena observed in the universe.