Second stage gets a lift
This image, taken in 1967, shows the rocket’s second stage, known as S-II, being lifted onto the A-2 test stand at NASA’s Mississippi facility, now known as the Stennis Space Center. During launch, the second stage kicked in once the first stage got discarded (first stages fell into the Atlantic Ocean), burning its five J-2 engines for roughly six minutes and taking the vehicle and payload to heights reaching 115 miles (185 km). Rockwell International Corporation built the S-IIs, which ran on a mixture of liquid hydrogen and liquid oxygen.
