There may well be more than 60 billion habitable planets littering the Milky Way, but it’s virtually impossible to make use of that figure. Instead, how about this picture, which shows you how many planets are within 60 light-years of Earth.
In the image, the size of the circle represents the size of the planet, while colour indicates the kind of star it orbits: dusky red signifies that it’s spinning around something similar to the Sun, grey means that the star is a different size. Dark circles represent planets the same size as Earth.
While it doesn’t quite match the 60 billion total of the Milky Way, it’s worth remembering that our galaxy happens to be a massive 100,000 light-years across, while this shows planets within 60. In other words, distances that — given the right technology — might one day be possible to travel. More compelling evidence, if it were required, that we’re probably not alone. [XKCD]