General Theory of Relativity

Imagine the whole world is a giant, bouncy trampoline. If you put a big, heavy ball in the middle, it makes a dip, right. I am that dip. I am a secret rule that keeps everything from floating away. Before anyone knew my name, they saw the moon go around the Earth and the Earth go around the Sun. They wondered why. I am the answer. The big, heavy Sun makes a deep curve in the trampoline of space, and the Earth just rolls around and around in that curve, like a little marble. I keep everything dancing together.

For a very long, long time, I was a big secret. No one could figure me out. Then, a very smart friend with fun, wild hair came along. His name was Albert Einstein. He thought and thought about me. On a special day, November 25th, 1915, he shared his big idea with the world. He said that gravity wasn't a magic pull. He said that I, the space all around us, could bend and curve. He gave me a very big name. He called me the General Theory of Relativity. It's a fancy way of saying that I am the bendy, stretchy rule that tells planets and stars where to go.

Even today, I am busy helping you. Do you ever ride in a car that uses a map to show you where to go. I help make those maps work just right so you can get to the park or your friend's house. That map system is called GPS, and it needs me to be super accurate. So the next time you look up at the bright moon and the sparkly stars, remember me. I am the wonderful, bendy rule that keeps our whole universe playing together in a beautiful, cosmic dance.