Countdown clocks tick toward 7:20 a.m. launch

Countdown clocks have picked up and are ticking toward one final built-in hold.

Launch of the Delta 2 rocket and NASA's Dawn spacecraft remains scheduled to blast off from Launch Complex 17B at Cape Canaveral Air Force Station at 7:20 a.m.

Clocks picked up at T-Minus 15 minutes at about 6:55 a.m. and will tick down to T-Minus 4 minutes. A final 10-minute built-in hold will follow.

The final countdown will pick up at 7:16 a.m. for the planned 7:20 a.m. launch.