It was, the IMAX mini-doc Roving Mars tells us, the equivalent of launching a basketball from Los Angeles to New York City and sinking the shot without hitting the rim. It was also, to stick with the sports metaphors, a ''300-million-mile interplanetary hole in one.'' In July 2003, two robot rovers bearing a mild resemblance to Short Circuit's Johnny Five zoomed across the universe and, six months later, landed right where they were supposed to...on the surface of Mars, where they proved conclusively that the planet once contained, as the oh-wow narration fetchingly tells it, ''wine red pools under a pink Martian sky.'' So maybe, 3 or 4 million years ago, there really was life on Mars. The mission is an impressive coup for NASA these scientists are smart! but it doesn't quite slam-dunk as a fully satisfying IMAX experience. The rovers radioed back real, IMAX-ready stills of Mars, but only a series of pics featuring a set of strange little nodes that look like blueberries planted in a pile of red rocks carry any kind of translatable otherworldly kick. The other true-life snaps get buried under a ton of CGI imagineering, which drains their impact. The real Mars, in this film anyway, doesn't compare with the fake one.