Since the 1960s, America’s Delta-type launch vehicles have been a dominant force in space exploration. This week marked the end of an era for these rockets as the U.S. Space Force and United Launch Alliance (ULA) retired the last Delta IV Heavy rocket after its successful launch on Tuesday from Cape Canaveral, Florida. The 23-story-tall rocket carried a ki spy satellite for a secret mission designated NROL-70, which successfully deployed satellites for the National Reconnaissance Office (NRO), a US defense intelligence agency.
Throughout its history, Delta-type rockets have launched a wide range of payloads, including the world’s first weather and GPS satellites, NASA science missions, Mars rovers, and communication satellites such as Echo 1A and Telstar 1. In retirement, the Delta and Atlas rockets will be succeeded by the new Vulcan rocket, which completed its first successful flight in January.
ULA, a partnership between Boeing and Lockheed Martin, is transitioning to the Vulcan rocket for future missions. The last Delta IV rocket weighed 733 tons when fully fueled and consisted of a lower stage with three boosters and a single-engine upper stage for orbital delivery. Atlas V rockets have 17 more missions booked before their scheduled retirement.
The retirement of the Delta-type rockets marks the end of an era in American spaceflight history. These powerful launch vehicles have played a crucial role in exploring our solar system and beyond, and their legacy will continue to shape future space missions for years to come.
