Posted: Wed, Mar 18, 2009, 7:30 AM ET (1130 GMT)
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The launch of a military communications satellite on an Atlas 5 rocket was postponed Tuesday evening after a leak developed in the rocket's upper stage. The Atlas 5 421 was scheduled to launch Tuesday night from Cape Canaveral and place the WGS 2 satellite into geosynchronous orbit. However, during fueling of the rocket a leak was detected in the oxidizer valve in the rocket's Centaur upper stage, and scrubbed the launch. No new launch date was immediately announced.