Insiders say the title change was hotly debated a year ago when the word "Mars" was verboten in the wake of Disney's March 2011 bomb Mars Needs Moms. According to several sources, the studio conducted a study of how the word would play with potential audiences. The results were pointed enough -- Disney's 2000 sci-fi film Mission to Mars and Warner Bros.' 1996 sci-fi comedy Mars Attacks! weren't hits, either -- that the studio stripped out mention of the red planet. ("It was the most ridiculous thing I've ever heard," says one person who was privy to the research.)