36,400,000. That is the expected number of intelligent civilizations in our galaxy, according to Drake’s famous equation. For the last 78 years, we had been broadcasting everything about us – our radio, our television, our history, our greatest discoveries – to the rest of the galaxy. We had been shouting our existence at the top of our lungs to the rest of the universe, wondering if we were alone. 36 million civilizations, yet in almost a century of listening, we hadn’t heard a thing. We were alone.