The sixth and final satellite in the U.S. military’s network of ultra-secure, nuclear-hardened AEHF communications relay stations has arrived in Florida for final preparations for liftoff in March on a United Launch Alliance Atlas 5 rocket, the first of nearly 20 U.S. Space Force missions planned for launch in the first year of operations for the new military service.

This is the launch timeline to be followed by the Atlas 5 rocket’s ascent into orbit from Cape Canaveral with the SBIRS GEO Flight 3 satellite for U.S. military infrared reconnaissance. Launch is scheduled for Thursday at 7:46 p.m. EST (0046 GMT).

A SpaceX Falcon 9 rocket lifted off from Cape Canaveral at 1:50 a.m. EDT (0550 GMT) Sunday with the Telstar 19 VANTAGE communications satellite, a powerhouse spacecraft designed to beam broadband and in-flight WiFi signals across the Americas and the North Atlantic. The rocket’s first stage successfully landed at sea aboard SpaceX’s drone ship.