MarketWatch: Ridley Scott’s latest science-fiction epic, “The Martian,” opened with a stellar $55 million weekend at the box office. The Matt Damon-led film from 20th Century Fox notched up the second biggest October opening weekend, just shy of first-placed “Gravity.” The earlier space disaster movie from Time Warner’s Warner Bros. earned $55.8 million in its debut weekend in 2013. “The Martian,” based on Andy Weir’s best-selling novel of the same name, is Fox’s biggest opening so far this year.