Delta 4

Delta 4-Heavy rocket deploys spysat on final planned mission from ‘Slick Six’

United Launch Alliance sent a triple-core Delta 4-Heavy with a top secret U.S. government spy satellite into orbit Saturday from California’s Central Coast, closing out a chapter in the tangled history of a launch pad originally built to support military astronaut missions on Titan rockets and space shuttles. Two more Delta 4-Heavy rockets are left in ULA’s inventory for launches in 2023 and 2024 from Cape Canaveral.

Delta 4

Live coverage: Delta 4-Heavy rocket launches from California

United Launch Alliance’s Delta 4-Heavy rocket lifted off from Vandenberg Space Force Base in California at 3:25 p.m. PDT (6:25 p.m. EDT; 2225 GMT) Saturday with a classified spacecraft for the National Reconnaissance Office, the U.S. government’s spy satellite agency. The heavy-lifter launched for the final time from California, with two more Delta 4-Heavy flights remaining from Cape Canaveral before the rocket’s retirement.