Live coverage: Atlas 5 countdown and launch journal

Freed from a legal restriction officials said limited its ability to compete for future U.S. military satellite launches, United Launch Alliance has ordered 20 new RD-180 engines from Russia that will keep the Atlas 5 rocket flying into the early 2020s.

A United Launch Alliance Atlas 5 rocket departs Vandenberg Air Force Base today at 10:30 a.m. local time (1:30 p.m. EST; 1830 GMT) to deliver the commercial WorldView 4 Earth-imaging satellite into polar orbit for DigitalGlobe.

The enigmatic X-37B spaceplane, launched into low-Earth orbit on an experimental military mission in 2015, continues to circle the planet despite a flurry of landing rumors.