NASA’s new moon rocket heads to launch pad for dress rehearsal

NASA’s new SLS moon rocket, the most powerful yet built, was cleared for rollout from its Kennedy Space Center processing facility Thursday, kicking off an 11-hour trip to the launch pad for a dress rehearsal countdown in early April to clear the way for a long-awaited maiden flight in late May or June.

The 322-foot-tall rocket, anchored to a 10-million-pound mobile launch gantry and…