“Unlocking the Secrets of the Moon: The Ingenious Strategies That Made NASA’s Historic Landing Possible”
The design and development of the Lunar Excursion Module – or simply the Lunar Module, as it was later renamed – is a huge subject worthy of its own separate video. However, we will attempt to summarize it here as best we can. Early on, engineers settled on a strange, insect-shaped vehicle comprising two main sections: a lower descent module with legs and a rocket engine to allow the vehicle to touch down on the lunar surface, and an upper ascent stage containing the pressurized crew cabin. The whole vehicle would be stored aboard the Saturn V rocket in a cone-shaped shroud or adapter just behind the Apollo CSM. After lifting off from the earth, the CSM, LM, and SIVB [“S-four-B”] upper rocket stage would enter a parking orbit around the earth, allowing the crew to make last-minute checks before making a Trans Lunar Injection or TLI burn to send them on their way to the moon. Shortly thereafter, the CSM would detach from the rocket stack, turn around, dock with the LM, and extract it from its adapter. Then, upon reaching lunar orbit, two astronauts – dubbed the Commander and the Lunar Module Pilot – would enter the LM through a short tunnel, undock from the CSM, and descend to the lunar surface, leaving the third crew member, the Command Module Pilot, orbiting overhead. On completion of the mission, the crew would fire the ascent stage engine, using the now-spent descent stage as a launch pad to send them back into orbit where they would rendezvous with the Command Module Pilot aboard the CSM. Once the crew were safely aboard the CSM, the LM ascent stage would be discarded and the CSM would fire its engines, sending the crew back towards the earth.
