Live coverage: Atlas 5 countdown and launch journal

NASA’s four Magnetospheric Multiscale mission spacecraft were encapsulated Feb. 23 in the United Launch Alliance Atlas 5 rocket’s nose cone at the commercial Astrotech processing campus in Titusville. Delivery of the payload to the Atlas 5 assembly building for mating occurred on Friday, Feb. 27.

SpaceX rolled out a reused Falcon 9 booster for a hold-down engine firing Wednesday at pad 40 at Cape Canaveral Air Force Station, making the first use of the launch complex since a rocket exploded there in September 2016. The static fire test accomplished Wednesday was a key step in preparations for launch of a space station cargo ship Dec. 12.

United Launch Alliance’s second-to-last Delta 4-Heavy rocket is scheduled to blast off from Cape Canaveral April 20 with a classified cargo for the U.S. government’s spy satellite agency, a mission that will mark ULA’s first flight of the year, officials announced this week.