ULA’s Delta IV Heavy rocket is preparing to hang up its engines after two decades of spaceflight.
Here and now: The rocket is targeting a 1:40pm ET liftoff from Cape Canaveral with a classified NRO payload on board. But Delta Heavy may live to launch another day—an update on Wednesday predicted just a 30% chance of good weather during the launch window.
Whenever it flies, it will be the 16th and final launch of the Delta IV Heavy.
Look back: The Delta IV Heavy lifted off on its first flight in December 2004, but the Delta fleet goes back much, much farther to 1960, when the first Delta rocket launched from Florida’s space coast.
The entire Delta family of rockets has notched nearly 400 launches. Thursday’s flight will be the final Delta variant to retire, marking the end of an era.
Highlights: The rocket has given a ride to some pretty high-profile passengers, including:
- The Orion capsule on its first uncrewed test flight
- The Parker Solar Probe, a scientific mission to study the Sun’s outer corona
Up next: Delta IV Heavy isn’t launching into the sunset without a successor ready to take its place. ULA’s new heavy-lift rocket, Vulcan, made its debut flight in January.