What is Planet X?

Caltech researchers have found evidence suggesting there may be a "Planet X" deep in the solar system. read more

The Caltech scientists believe Planet X may have has a mass about 10 times that of Earth and be similar in size to Uranus or Neptune. The predicted orbit is about 20 times farther from our sun on average than Neptune (which orbits the sun at an average distance of 2.8 billion miles). read more

Nibiru cataclysm. The Nibiru cataclysm is a supposed disastrous encounter between the Earth and a large planetary object (either a collision or a near-miss) which certain groups believe will take place in the early 21st century. Believers in this doomsday event usually refer to this object as Planet X or Nibiru. read more

Brady claimed that they could have been caused by a Jupiter-sized planet beyond Neptune at 59 AU that is in a retrograde orbit around the Sun. However, both Marsden and Planet X proponent P. Kenneth Seidelmann attacked the hypothesis, showing that Halley's Comet randomly and irregularly ejects jets of material, causing changes to its own orbital trajectory, and that such a massive object as Brady's Planet X would have severely affected the orbits of known outer planets. read more

Lieder first made the connection between Nibiru and her Planet X on her site in 1996 ("Planet X does exist, and it is the 12th Planet, one and the same."). However, Sitchin, who died in 2010, denied any connection between his work and Lieder's claims. read more