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In 2006 the International Astronomical Union (IAU) agreed on a controversial definition of the word "planet," which included the criterion that a planet must have cleared the neighborhood around its orbit. That condition struck Pluto from the roster of planets, demoting it to dwarf planet status, because Pluto accounts for only a fraction of the mass of the bodies in its orbital zone.
Pluto's demotion to the minor leagues spawned heated debate, as well as the requisite protest T-shirts and conspiracy theories. Now it's the subject of legislation in the Illinois Senate, which recently adopted a resolution declaring that Pluto had been unfairly downgraded. As such, lawmakers proclaimed that Pluto is now "reestablished with full planetary status, and that March 13, 2009 be declared 'Pluto Day' in the State of Illinois in honor of the date its discovery was announced in 1930."
That discovery, of course, came courtesy of Illinois native Clyde Tombaugh, who was born on a farm near the town of Streator in 1906. But what jurisdiction does a state legislature have over such matters, other than looking to preserve the legacy of a local boy made good? That's simple. According to the resolution, "Pluto passes overhead through Illinois's night skies." No word yet on whether similar logic will be used to annex the moon for the Land of Lincoln.
Photo of Pluto-themed donation bin at Lowell Observatory in Arizona, where Clyde Tombaugh discovered Pluto in 1930, courtesy of phoenixdailyphoto on Flickr