After 17 years and 29 missions, the final Delta 4 rocket to ever fly in a medium configuration soared over the Space Coast one last time Thursday morning.
Launch provider United Launch Alliance is phasing out the class of rockets as it prepares to debut its Vulcan Centaur rockets from with launches from Kennedy Space Center as early as April 2021. ULA already phased out its lighter lift vehicle, the Delta 2, in September 2018. The third variant, Delta 4-Heavy, still has five more missions ahead before it, too, is taken out of circulation. Read more here.