Video: Falcon 9 fires up engines for static fire test (members only)

Astronaut Scott Kelly, in good spirits and looking surprisingly fit after a record 340 days in space, said Wednesday he could have stayed up longer if necessary, giving him confidence future astronauts will be up to the challenge of even longer flights to Mars and beyond.

The Centaur upper stage launching the Cygnus space freighter Tuesday persevered through a velocity shortfall from the first stage of the Atlas 5 rocket, improvising with a longer firing to reach the correct orbit.

Disconnected from the International Space Station berthing port and then cast free by the robotic arm, the commercial Cygnus cargo craft flew away Friday after successfully restarting U.S. resupply service to the outpost.