The schedule remains tight but optimism continues to run high that NASA will launch a pair of probes toward Mars from Cape Canaveral Air Force Station in June. “If things keep going without any surprises that’s still very achievable,” Kennedy Space Center spokesman George Diller said Thursday. There’s no padding left in the schedule to deal with any major last-minute problems and still make the targeted June 5 launch of the combined Mars Exploration Rover (MER)-A vehicle and MER-2 rover. The schedule is a little less hectic for the targeted June 25 launch of the combined MER-B vehicle and MER-1 rover.