As a kid, Arnie Rubin pretended he journeyed to Mars with Flash Gordon. As an adult, he can pretend with a more realistic explorer. As owner of Code 3 Collectibles, a model maker known for its fire trucks and “Star Wars” replicas, he’s watched the development of a hyper-accurate miniature of NASA’s Jet Propulsion Laboratory’s Mars rovers. For the past 10 months, his designers have crafted an articulated, rolling 1-10 scale version of the Spirit and Opportunity rovers, highly detailed toys for adult space enthusiasts.