The Secret Behind Earth's Orbit

By: Naviya Alwar-

Every day, the Earth travels in a near perfect circle around the Sun at around 30km/sec, while spinning counterclockwise at 1600km/hr. But, how do we not feel this motion as we go through our daily life? The answer: gravity and inertia.

Gravity, a fundamental concept of physics, is stronger than you think. This force is the sole reason our planet stays in the 'Goldilocks zone', a sector of our galaxy capable of sustaining life. Specifically, our Sun's constant gravitational pull draws the Earth toward its center, preventing it from drifting off out of the zone. But, if the Sun's gravity is constantly pulling us closer to it, then how do we stay in our orbit? This is where inertia comes into use. The concept of Inertia comes from Newton's first law, stating that an object in motion will stay in motion with the same speed and direction unless acted upon by an external force. Going back to the formation of the Earth 4.5 billion years ago, the Earth was formed under intense heat and its own gravity, causing it to spin rotationally and then orbitally around the Sun. Unlike moving objects on Earth (where moving objects will slow due to friction) there is no friction in space for objects in motion. Therefore, the Earth currently continues to spin with the same momentum our planet was formed with and will for the rest of its long life.