CAPE CANAVERAL, Fla. — A Delta 4 rocket blasted off from Florida on Wednesday to deliver the ninth of 12 next-generation Global Positioning System satellites into orbit.
The 207-foot-tall (63-meter-tall) booster, built and flown by United Launch Alliance, bolted off its seaside launch pad at Cape Canaveral Air Force Station, marking the third launch in 25 days from the nation’s busiest spaceport.

ULA is a partnership of Lockheed Martin and Boeing. Three more of the Boeing-built GPS 2F satellites remain to be launched over the next 10 months, completing an orbital network that provides military, civilian and commercial radio signals for precision navigation and timing. The 2F series, which cost most than $122 million each, feature improved clocks, more power, longer lifetime and added signals.
The three remaining 2F satellites will be launched on ULA's lower-cost Atlas 5 rockets. ULA intends to phase out medium-lift versions of the Delta 4 rocket, which are used to fly GPS and similarly sized spacecraft, to compete more effectively against California-based SpaceX, whose Falcon 9 rockets are about half the price.