Live coverage: Atlas 5 blasts off from California

Flight controllers at NASA’s mission control center in Houston have completed the robotic swap out of a failed power distribution unit outside the International Space Station, clearing a hurdle ahead of Friday’s predawn launch from Cape Canaveral of a SpaceX supply ship.

With the Atlas 5 rocket that will boost it into space now assembled and waiting, a $408 million NASA communications satellite is in final preparations for its science data relay mission.

America’s next Mars rover, a $2.1 billion nuclear-powered vehicle to search for evidence that life once existed there, will be launched to the Red Planet in the summer of 2020 by a powerful Atlas 5 rocket.