For the more orthodox proponents of the modern day Ancient Astronaut Theory, the existence of Nibiru is one of the primary tenets. According to theory, Nibiru is a planet in the Sol system that is or was once populated by a race of beings. These beings were depicted in Sumerian cuneiform and are known as the Anunnaki here on Earth. One of the favorite arguments of skeptics and debunkers alike, is that even if a planet on a highly elliptical orbit did exist, there is no way life could be supported on such an icy cold planet. Ironically, you will not find to many folks in the scientific community making such an argument.