An Orbital ATK Minotaur 4 rocket partially powered by modified motors from a Cold War-era nuclear missile lifted off early Saturday from Cape Canaveral with a small U.S. military satellite to help track other objects in space. The solid-fueled launcher took off at 2:04 a.m. EDT (0604 GMT) after a weather delay.

Mission managers Tuesday granted approval to proceed with Wednesday’s rollout of the Atlas 5 rocket and Thursday’s launch to deliver the commercial Cygnus cargo ship into orbit to resupply the International Space Station.

SpaceX will go for another first Thursday, this time flying a refurbished Dragon supply ship carrying nearly 6,000 pounds of cargo and experiments to the International Space Station nearly three years after its first mission.