At times, usually after reading a good science fiction book I wonder if we are alone in the universe. But then I kick myself. The answer is known. We don't have to wonder. It's been calculated using a formula called the Drake equation. Click HERE and go to the video at the end to understand what I'm talking about. Three years before I was born, a man name Frank Drake figured it out using Boolean logic. The current best estimate is that there are 50,000 other life sustaining planets in our galaxy with conditions suitable for the evolution of intelligent life forms.