Video: Tower rollback prior to launch of Mars Pathfinder atop a Delta 2

Here’s a look by the numbers of the previous Delta 4 flight history and the remaining flights of the rocket named Delta.

The next-to-last Delta 2 rocket is being stacked at its California launch site to take flight in January to put a civilian weather satellite into polar orbit.

United Launch Alliance engineers filled a Delta 4-Heavy rocket with super-cold liquid hydrogen and liquid oxygen propellants Friday at Cape Canaveral Air Force Station during a practice countdown before the heavy-lifter’s scheduled liftoff in June with a top secret U.S. government spy satellite.