Here's why:

* Newton's Law of Universal Gravitation: Newton formulated the law of universal gravitation, which describes the force of attraction between any two objects with mass. This law is fundamental to understanding how planets orbit the sun, how the moon orbits the Earth, and many other celestial phenomena.

* Apple Story: While the story of the apple falling on Newton's head is likely apocryphal, it's a popular way to illustrate his inspiration for thinking about gravity.

* Influence on Physics: Newton's work on gravity revolutionized our understanding of the universe and laid the foundation for modern physics.

While Newton made groundbreaking contributions to our understanding of gravity, other scientists have also played significant roles in this field. Some notable examples include:

* Albert Einstein: Developed the theory of general relativity, which provides a more accurate and comprehensive description of gravity than Newton's theory, especially in strong gravitational fields.

* Galileo Galilei: Made crucial observations about the motion of objects, which led to the development of the concept of gravity.

* Johannes Kepler: Formulated Kepler's Laws of Planetary Motion, which describe the elliptical orbits of planets around the sun, a key factor in understanding gravity.

These scientists, and many others, have contributed to our understanding of gravity, making it one of the most studied and fascinating forces in the universe.