A ULA Delta IV Heavy rocket has completed its penultimate mission in its history, sending a secret US spy satellite into orbit

United Launch Alliance (ULA) this week successfully completed the penultimate mission in the history of the Delta IV Heavy rocket. The NROL-68 mission was designed to put a US reconnaissance satellite into orbit.

Here's What We Know

The payload was a US National Reconnaissance Office spy satellite. ULA was unable to send the spacecraft into orbit on time due to technical problems. But with a one-day delay, the NROL-68 mission took place.

US intelligence has a large constellation of satellites whose technical parameters are classified. Our hero was no exception. Because of this, ULA launched the mission broadcast almost 7 minutes after launch, at the request of the US National Intelligence Agency.

Delta IV Heavy has a height of 71.6 metres and generates more than 950 tonnes of thrust at launch. By comparison, the Space Launch System (SLS) for the Artemis lunar programme has about 4,000 tonnes of thrust, and SpaceX Starship will have over 7,500 tonnes with the current generation Raptor satellites.