An orbit like that of Nibiru within our planetary system is inconsistent with celestial mechanics. David Morrison, NASA space scientist explains that after just one previous flyby of Earth, such as they claim happened in Sumerian times, Earth itself would no longer be in its current near circular orbit and would be likely to have lost its Moon. If Nibiru were a brown dwarf it would have even worse effects, as brown dwarfs are far more massive. Since Pluto is now frequently observed by backyard telescopes, any giant planet beyond Pluto would be easily observed by an amateur astronomer. And if such an object existed in the Solar System, it would have passed through the inner Solar System a million times by now.