Here's why:
* Gravity is a force of attraction between any two objects with mass. The Sun has a massive amount of mass, so it exerts a strong gravitational pull on the planets.
* This pull keeps the planets from flying off into space in a straight line. Instead, it constantly pulls them towards the Sun, causing them to follow a curved path – an orbit.
* The planets also have their own velocity (speed and direction), which causes them to move forward and "miss" the Sun as they fall towards it. This balance between gravity pulling inward and velocity moving forward is what creates a stable orbit.
Think of it like a ball on a string:
* The string represents gravity, pulling the ball towards your hand (the Sun).
* The ball's movement in a circle represents the planet's orbit.
* If you let go of the string, the ball would fly off in a straight line (like a planet escaping the Sun's gravity).
So, gravity is the key player in keeping planets orbiting the Sun.
