Live coverage: Vega rocket deploys second Sentinel satellite

A United Launch Alliance Atlas 5 rocket blasted off from Vandenberg Air Force Base in California at 5:49 a.m. local time (8:49 a.m. EDT; 1249 GMT) Thursday on the classified National Reconnaissance Office NROL-55 mission.

Europe’s LISA Pathfinder mission — a fundamental physics lab launched last year to a point a million miles from Earth — has demonstrated the mind-boggling technology required for a future space-based observatory to listen for faint, low-frequency vibrations emitted by invisible objects in the most distant pockets of the universe, scientists said this week.

Two U.S.-built communications satellites rode the 100th European-made Ariane 5 rocket into orbit Tuesday from the jungle of French Guiana. Liftoff occurred at 2238 GMT (6:38 p.m. EDT) after a 45-minute delay caused by a range technical problem.