Video: Weather causes Atlas 5 countdown hold

United Launch Alliance ground crews are putting the final touches on a Delta 4 rocket scheduled for blastoff Friday evening from Cape Canaveral with a U.S. Air Force communications satellite.

United Launch Alliance’s next Atlas 5 rocket moved to its launch pad Wednesday at Cape Canaveral, taking position for liftoff with the U.S. military’s sixth and final Advanced Extremely High Frequency secure communications satellite.

Fresh off its first terrestrial test drive, NASA’s Mars 2020 rover was displayed to media last week at the Jet Propulsion Laboratory in California before it’s packed up and flown across the country to Cape Canaveral in February to begin final launch preparations for liftoff in July.