On this Date in 2006...

...the International Astronomical Union (IAU) redefines the term "planet" such that Pluto is now considered a Dwarf Planet.  Pluto is later seen peeing on the head of the IAUs leg in protest.

On this Date in 1781...

...German-born British astronomer and composer William Herschel discovered the planet Uranus while in the garden of his house in Bath, Somerset, England, thinking it was a comet.  Though to be fair, when ur back end is that big, it is not that uncommon for it to be mistaken for a planet.