There are a host of engineering problems that must be faced in order to safely transit astronauts to and from the moon. Key challenges include:
1. Takeoff Generating enough force to escape Earth's gravity requires enormous energy.
2. Propulsion Ensuring enough fuel is available to return to Earth.
3. Artificial Environment Creating an artificial life support system for the occupants of the ship. This must supply oxygen, filter out surplus carbon dioxide, provide heating, radiation shielding and a perfect seal to protect the occupants from the cold vacuum of space.
4. Food and water Ensuring enough supplies are packed to keep all the occupants alive during the multi-day trip.
Some problems that needed to be overcome in order for NASA to be able to land men on the moon and return them safely were, A new, larger rocket had to be developed to get the Apollo Command Module, Lunar Orbiter, and LEM (Lunar Excursion Module) into orbit. Additional engines had to get the whole package on the way to the moon. Eventually, the Saturn V rocket was created to achieve this purpose. Then, there had to be a way to land the LEM safely onto the lunar surface and return it to the Lunar Orbiter.
