Planet X

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Planet X

As yet undiscovered tenth planet of our solar system. Whether the hypothesized and occasionally observed but never confirmed planet Vulcan inside the orbit of Mercury, or the largest asteroid, Ceres, or some very large Kuiper Belt Object, current astronomers can't even seem to decide if we have a ninth planet yet, as dispute has arisen, now that more KBOs are being discovered, as to whether the planet Pluto is actually a planet, or just a very very very large comet.