* Gravity: The Sun's gravity pulls on the Earth, trying to pull it in. This is the force that keeps us in orbit.
* Inertia: Inertia is the tendency of an object to resist changes in its motion. The Earth is already moving in a direction perpendicular to the Sun's gravitational pull. This sideways motion, combined with the Sun's gravity, creates a curved path – an orbit.
Imagine throwing a ball tied to a string. The string acts like gravity, pulling the ball towards your hand. But the ball also has sideways motion, making it go in a circle. If you let go of the string, the ball will fly off in a straight line, but while the string is attached, it's forced to go in a circle. The Earth is like that ball, constantly pulled towards the Sun by gravity, but also moving sideways due to inertia.
Here's a simple analogy:
* Imagine a car driving around a roundabout. The car wants to go straight ahead (inertia), but the steering wheel (gravity) keeps it turning in a circle.
The Earth is constantly falling towards the Sun, but its sideways motion keeps it from actually hitting it. This is what keeps us in orbit.
