"Dark Jupiter" may haunt the edge of the solar system

Perhaps the hypothetical Planet X - a theoretical gas giant beyond Neptune suggested by astronomer Percival Lowell - is real after all. In fact, "a century of comet data suggests a dark, Jupiter-sized object is lurking at the solar system's outer edge and hurling chunks of ice and dust toward Earth." From Wired Science:

In 1999, Matese and colleague Daniel Whitmire suggested the sun has a hidden companion that boots icy bodies from the Oort Cloud, a spherical haze of comets at the solar system's fringes, into the inner solar system where we can see them.

In a new analysis of observations dating back to 1898, Matese and Whitmire confirm their original idea: About 20 percent of the comets visible from Earth were sent by a dark, distant planet.

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