Hunting for the real 'Planet X' › Analysis (ABC Science)

In Depth › Analysis Hunting for the real 'Planet X' Ghostly planet Recent discoveries of exoplanets are raising the question whether astronomers have found all the planet-like objects in our own system. The hunt for Planet X began in 1781 when British astronomer Sir William Herschel was studying stars in the constellation of Taurus and noticed one star seemed slightly fuzzy or nebulous in appearance. The search for the ninth planet in the solar system began and it was American astronomer Percival Lowell who identified possible candidates. This could have been the end of the Planet X saga, but recent studies of the Kuiper Belt - a region of icy minor planets located in the outermost reaches of the solar system - suggest this may not be the case.