George Smoot

For many centuries, humans have speculated that there might be planetary systems around other stars and that there could be extraterrestrial life there and even intelligent being. However, those were simply speculations, and now we have evidence for the first part of these ideas.

Every time you log in to Facebook, every time you click on your News Feed, every time you Like a photo, every time you send anything via Messenger, you add another data point to the galaxy they already have regarding you and your behavior.