On August 22nd, the United Launch Alliance is set to fly the very last mission of its Delta IV Medium rocket, a single-core vehicle that’s been launching to space since 2002. This final flight will be the 29th mission of the Delta IV Medium. The car is now being retired as ULA works to consolidate its technology and develop a new generation of rockets.



The Delta IV is the last remaining descendant of the Delta family of rockets, a long line of vehicles that date back to the birth of the modern space era. The original Deltas, built by the Douglas Aircraft Company (now part of Boeing), were derived from an old Air Force ballistic missile called Thor. The first successful Delta launch occurred in 1960, lofting a communications satellite into orbit for NASA. Since then, the vehicles have been modified and updated dozens of times, resulting in the Delta IV that’s flying today.

ULA, a joint partnership between Boeing and Lockheed Martin, has been flying two primary versions of the rocket for the last two decades: the Delta IV Heavy, the company’s most powerful vehicle, which consists of three rocket cores strapped together, and the Delta IV Medium, which is defined by a single-core car. While it relies on a single-center, the Medium does boast numerous configurations that include smaller strap-on boosters for an extra push. This final mission will consist of two of these boosters on either side of the rocket.

The Delta IV Medium’s final flight is scheduled for takeoff sometime within a 27-minute launch window, between 9 AM ET and 9:27 AM ET on August 22nd. The vehicle will be flying out of ULA’s launchpad at Cape Canaveral Air Force Station in Florida. Live coverage should begin around 8:30 AM ET, so check back then to see this rocket take to the skies one last time.