Q&A with Tim Ellis, CEO and co-founder of Relativity Space (members only)

A replay of the United Launch Alliance Atlas 5 rocket launching the Air Force’s X-37B reusable spaceplane from Cape Canaveral, Florida.

Slung under the belly of a specially-equipped carrier airplane, a Northrop Grumman Pegasus rocket took off Wednesday from Vandenberg Air Force Base on a two-day trek to a remote U.S. military test site in the Pacific Ocean, where crews will ready the air-dropped booster for launch of a NASA research satellite next week.

SpaceX’s second Falcon Heavy, outfitted to produce more thrust than the heavy-lifter’s debut flight last year, was raised vertical at launch pad 39A in Florida on Wednesday ahead of a launch attempt with the Arabsat 6A communications satellite.