The Evolution of Gravity

Astronomers, as we go through history, started recording the position of planets in the sky. And if you record this for enough time and you start really thinking hard about it, you start to understand some patterns of things that are happening. This was an idea that was around, around the 17th century, um, maybe before that as well. It was the idea that there are two different types of gravity. There's terrestrial gravity, gravity here on earth that pulls things towards the earth, the center of the earth, and then there's a different gravity, celestial gravity that governs the motion of heavenly bodies around,. around the sun.