Gravitational Waves

Gravitational waves are ripples that travel through space. They are made by very big events like two black holes crashing together. Albert Einstein said these waves should exist back in 1916. Scientists did not actually detect one until 2015. The waves stretch and squeeze space as they pass by.

Einstein's Idea

Einstein came up with the theory of general relativity. This theory says that gravity is how space bends. When big objects speed up or crash, they shake space itself. The shakes travel outward as waves. The waves move at the speed of light.

Catching the Waves

A special tool called LIGO was built to find gravitational waves. LIGO uses lasers that are miles long. It can measure changes smaller than the width of an atom. The first wave LIGO found came from two black holes smashing together. It happened 1.3 billion years ago.

Fun Facts

• The first gravitational wave was detected on September 14, 2015.
• The scientists who found them won the Nobel Prize in 2017.
• Gravitational waves pass right through Earth without being stopped.

Did You Know?

When gravitational waves reach Earth, they change the length of things by less than the width of a single proton.