Photos: Atlas 5 rolls out for Friday launch to GPS constellation

The 377th Delta rocket begins its journey to space carrying a military communications satellite funded by Canada, Denmark, the Netherlands, Luxembourg and New Zealand in a deal that gives the allies access to the U.S. military’s worldwide Wideband Global SATCOM system.

SpaceX test-fired a Falcon 9 rocket for the second time Saturday after replacing a valve following an earlier static fire test Wednesday. The move has postponed the Falcon 9 rocket’s launch with the Amos 17 commercial communications satellite to no earlier than Tuesday.

A new launch date has been established — June 9 — for the Delta 4-Heavy rocket to carry a classified satellite into space for U.S. national security needs.