On Tuesday (May 10), NASA’s Kepler mission announced that it had nearly doubled the number of exoplanets we’ve discovered. Based on this data, NASA scientists expect there are tens of billions of Earth-like planets just in our own galaxy. That, however, might be really bad news for humanity. Ever since humans grasped the reality that we live on a tiny planet in a vast universe, we’ve wondered whether there is intelligent life elsewhere.

A simple equation, called the Drake equation, is the best way we have to estimate how many intelligent civilizations exist in a galaxy. When the equation was developed, one of the factors in it was how many planets existed around other stars. Because we didn’t have any direct proof of the existence of exoplanets, astronomers made conservative estimates. READ MORE