Before 2006, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto were considered as planets.
The first notable suggestion came from Kyle Sullivan of Lumberton, Mississippi, USA, whose mnemonic was published in the Jan. 2007 issue of Astronomy magazine: "My Violent Evil Monster Just Scared Us Nuts".
[7] Others angry at the IAU's decision to "demote" Pluto composed sarcastic mnemonics in protest: In 2007, the National Geographic Society sponsored a contest for a new mnemonic of MVEMCJSUNPE, incorporating the then-eleven known planets and dwarf planets, including Eris, Ceres, and the newly demoted Pluto.
On February 22, 2008, "My Very Exciting Magic Carpet Just Sailed Under Nine Palace Elephants", coined by 10-year-old Maryn Smith of Great Falls, Montana, was announced as the winner.
[12] Since the National Geographic competition, two additional bodies were designated as dwarf planets, Makemake and Haumea, on July 11 and September 17, 2008 respectively.