Video: Atlas/Cygnus pre-launch news conference

Kirk Shireman, NASA’s program manager for the International Space Station, is retiring from the space agency later this month to take a position in private industry.

SpaceX plans two Falcon Heavy launches this year for the U.S. Space Force in July and October, and United Launch Alliance has four national security space missions on its 2021 schedule, according to a military spokesperson.

Launching the Wideband Global SATCOM 8 satellite for the U.S. military, a United Launch Alliance Delta 4 rocket thundered away from Cape Canaveral at 6:53 p.m. EST (2353 GMT).