Watch the astronauts give a tour of their new Crew Dragon spacecraft

The main engine rumbling to life. Ice shards breaking free. The rocket lumbering off the pad. The battle against gravity being won once again. That was the scene as the Atlas 5 took flight to cap a generation of Global Positioning System satellites.

A SpaceX Falcon 9 rocket launched at 4:25 p.m. EST (2125 GMT) Wednesday from Cape Canaveral with the GovSat 1 communications satellite, a military-grade craft to relay signals for Luxembourg and allied nations. SpaceX’s launch team scrubbed an attempt Tuesday to replace a transducer on the company’s Falcon 9 rocket and wait for improved weather conditions.

A Soyuz rocket launched Friday with four commercial satellites to expand broadband Internet coverage in remote parts of the world, climbing into orbit from the Guiana Space Center positioned on the northeastern shore of South America.