Live coverage of Delta 4 countdown and launch

Astra was gearing up for the first orbital test flight of its small satellite launcher, named Rocket 3.0, from Alaska on Monday, but officials scrubbed the launch after detecting a problem with a guidance, navigation and control system in the final minute of the countdown. Poor weather at the launch site also prevented liftoff over the weekend on the first of two missions under the auspices of DARPA’s Launch Challenge.

A SpaceX Falcon 9 rocket lifted off from Space Launch Complex 4-East at Vandenberg Air Force Base in California at 12:17 p.m. EST (9:17 a.m. PST; 1717 GMT) Saturday with an oceanography satellite jointly developed by U.S. and European space and weather agencies. The rocket’s first stage booster returned to a bullseye landing back at Vandenberg.

An Ariane 5 rocket has blasted off from a tropical launch pad in French Guiana on nearly 3 million pounds of thrust, hoisting two U.S.-built communications satellites to orbit for commercial owners in Brazil and Japan.