Vulcan Centaur

Vulcan Centaur is United Launch Alliance's modern launch vehicle, developed to replace both the Atlas V and Delta IV families with a single, lower-cost rocket. Its first stage is powered by two Blue Origin BE-4 methane-fuelled engines, supplemented by up to six strap-on solid rocket boosters, and it carries the high-energy Centaur V upper stage.

Designed primarily to launch US national-security payloads, Vulcan flew its certification missions and was certified by the US Space Force for the most demanding national-security orbits. It is configured by the number of solid boosters and the fairing size.