Albert Einstein

An L-shaped machine in Louisiana is hunting for some of the most powerful waves in existence: gravitational waves. This wave detector acts like a giant tape measure to capture bends in space and time.

Behind the headlines and news conferences announcing the discovery were decades of hard work, hundreds of scientists and more than a billion dollars in taxpayer funds.

For decades, astronomers believed there was another planet in our solar system, tucked just out of sight. Then Albert Einstein figured out it wasn't there. Author Thomas Levenson explains.