You don't read. Allow me a hobbyist rocket nerd to explain it to you. Envision rockets as canons. What rocket canons do is fire a projectile payload up a mountain. The height of a low earth orbit mountain is a known distance. Boom a certain size Canon can fire a certain size projectile to the top of the low earth orbit mountain. Getting down again is easy as you might imagine. Gravity does the work after a little push to get you started. The moon Isa much taller mountain Take the fact below to the bank. Millions of people know this to be true. The saturn v was a Canon large enough to launch the odessy/lunar payload to the moon mountain top. And that is all it takes. Everything else is just keeping people alive through the process. And you already said yourself that we can keep people alive I space. The saturn v was a 110m 3000 ton single use Canon. Twice the size of the largest Canon in use today 50 years later Be proud of your ancestors.