Yahoo! Contributor Network - Wed, Dec 5, 2012 3:49 PM ESTWe lost many celebrities in 2012, some of whom made a permanent mark in the entertainment industry. Most recently, former "Dallas" star Larry Hagman passed away at the age of 81 while in the hospital battling throat cancer. Hagman rose to fame for portraying the super villain J.R. Ewing on "Dallas," which quickly became a top-rated television series in the late 70s. In his autobiography, Hagman insists the notorious role was not a primary focus on "Dallas" until he brought the character to life through ad-libbing on the set of the show. More »Iconic Celebs We Lost in 2012