The search for life on other worlds has been enduring for more than 50 years; fore fronted by SETI and Dr Frank Drake. The chance of life existing on other worlds is something that seems almost to be certain as there are billions of planets in our galaxy alone and there are billions of galaxies in the observable universe. However it may be the case that Earth is a unique and special place meaning that there are no other civilizations out there.
The Drake equation describes the chances of another intelligent civilization living out there by taking into account many factors. These include the chances of an Earth sized planet orbiting a yellow dwarf within the “goldilocks zone” and whether the civilization could have actually destroyed itself and many more.
Since this documentary was made the Kepler telescope has been launch into space. Over the last few years it has been bringing us in untold amounts of data about planets in other solar systems.