The United Launch Alliance is planning for the Vulcan to become its workhorse rocket. It faces its biggest test yet in its next launch.

Update, 3:25 p.m.: The Delta IV Heavy rocket launched from Vandenberg Space Force Base. Update, 3:20 p.m.: The mission director gave the final go for launch after all parties had check in with “go” ...

A spacecraft dubbed "the Vulcan" has embarked on its first national security mission and just its third flight ever from Florida. But plenty more launches should be in the spacecrafts' future – ...