The third stage
Saturn Vs also featured a third stage, known as IV-Bs, which featured a single engine that kicked in roughly 12 minutes after launch to send the Apollo crews into Earth orbit and then onto their treks toward the Moon. The image above, taken on October 11, 1968, shows the fully retracted Lunar Module Adaptor at the top of the third stage. During missions to the lunar surface, the adapter carried the Lunar Module (LM) to space. The McDonnell Douglas Astronautics Company built the IV-Bs for NASA. Fun fact: Five third stage Saturn V boosters are still in space.
