Planet X, or Nibiru, is on a crash course with Earth, doomsayers believe — prophecies draw new focus with 'Planet Nine' discovery. The planet, according to Caltech researchers, has a mass about 10 times that of Earth and takes about 15,000 years to make a full orbit around the sun. Doomsayers have prophesized for decades about a giant, rogue planet in our solar system that has the capability of colliding or passing near earth. Now it seems that it may be fast approaching the Earth, with it's arrival estimated at several weeks to several months.