15-02-2016 15:00

One hundred years ago, Einstein formed his theory of relativity. He also told us that space and time respond to matter within it. It is like putting your finger into a pond and moving your finger – you create water waves.

The same thing happens with space and time. When mass moves through space-time, it creates gravitational waves. We knew about these waves for a hundred years, but only this year, people detected them.

This is a great moment in the history of science. Four hundred years ago, Galileo looked to the sky and opened the age of modern astronomy. Now, we are entering the age of gravitational astronomy.

Difficult words: respond (to react), matter (material, thing), detect (to measure, to notice, to see).

You can read the original story and watch the video in the Level 3 section.