Is planet X real? Please cite information if it is factual.

Planet X is the name that was given to yet to be
discovered unknown planet. The possibility of existence of such a planet was based o
some apparent discrepencies observed in the orbits of gas giants Uranus and Neptune.
Perceival Lowell proposed his Planet X hypothesis in early twentieth century based on
this. For many years after that the existence of Planet X was considered a by reputed
scientists to be a very likely reality. Discovery of Pluto in 1930, further increased
the belief of scientists in reality of Planet X. Many attempts were made to locate this
planet and to determine its details. However no conclusive evidence could be found.
Finally in 1990 a study of measurements made by the Voyager 2 established that
irregularities observed in Uranus's orbit were due to overestimation of Neptune's mass.
With this serious speculation among scientific community about existence of Planet X
came to and end. href="http://en.wikipedia.org/wiki/Planets_beyond_Neptune#cite_note-standage-2"/> href="http://en.wikipedia.org/wiki/Planets_beyond_Neptune#cite_note-IAU-3"/>

Now
scientist agree that Planet X, as envisaged originally, does not exist. However the term
Planet X is used by many scientist for any other undiscovered
planet in the outer Solar System.