NASA’s Artemis Space Launch System (SLS) rocket rolled out front and center at the Kennedy Space Center two weeks ago. Friday night, NASA officials kicked off two days of testing.The SLS is being taken through what’s called a wet dress rehearsal. On Saturday, teams will march through a launch day routine, including fueling the massive tanks.There will be built-in pauses or holds so engineers can review data along the way.And then on Sunday, the countdown will restart, clicking toward a 2:40 p.m. launch window. Everything will be as a real launch until just before ignition.And then in about a week after the tests are done, we should be hearing about a launch date. For now, the earliest possibility is June.