The third Space Base Infrared Systems Geosynchronous Earth Orbit, or SBIRS GEO Flight 3, was hoisted atop the Atlas 5 on Jan.12 to complete the pre-flight assembly of the 189-foot-tall rocket for launch.

SpaceX’s Falcon 9 rocket is set for liftoff from Cape Canaveral on Monday, heading due east over the Atlantic Ocean to deliver the JCSAT 18/Kacific 1 communications satellite into orbit around 33 minutes later.

Astra was gearing up for the first orbital test flight of its small satellite launcher, named Rocket 3.0, from Alaska on Monday, but officials scrubbed the launch after detecting a problem with a guidance, navigation and control system in the final minute of the countdown. Poor weather at the launch site also prevented liftoff over the weekend on the first of two missions under the auspices of DARPA’s Launch Challenge.