NASA estimates that there are 10 billion small terrestrial (Earth-like) planets in our Milky Way Galaxy alone. Let’s take an extremely conservative guess and say that .0001% of these planets support life. That would mean there are 10,000 planets in our galaxy alone which support alien life. 

Oh yeah, there are about 500 billion galaxies in our universe. Do the math.

Blows the mind, huh?