How could the americans launch their sapceship from the moon, to go back to earth?

The launch pad was the base of the lunar lander module. It was a two-part spacecraft. The bottom half, or the descent stage, was a motor and four legs and holders for the experiment packages, and later, the lunar rover vehicle. When the lunar lander set down, the upper part had its own engine half inside its crew compartment.

When it was time to lift off the moon and return to the command capsule in orbit overhead, the astronauts lit the ascent engine, and the lander blasted up and away from the descent stage (the legs and stand and engine). There was a TV shot of that from the lunar rover on the third landing mission. Here is the YouTube video link: http://www.youtube.com/watch?v=AXs4tncQcAE

It's because the vehicle that the 2 moon astronauts were in was a lot smaller and lighter than the vehicle that they had to have to get the whole operation in space from earth. And the moon has much, much less gravity than that of earth. It takes a lot of power to escape the earth's gravity. And every time you add more propulsion, you add more rocket ship to carry the propulsion and that takes more propulsion for the added rocket ship, etc,etc. On the moon you only had 2 astronauts and a small 2 man escape vehicle. The lander was left along with the excursion vehicle. That means 2 people plus a small escape module and only 1/8th gravity and the propulsion was used up immediately so that was not much of a factor.

No, the flag is a lot too small and too a great way. Even our superb and greatest present day telescopes (Hubble and larger) might render a soccer stadium sized merchandise as a single pixel. To get your self an impression, inspect Google Earth and spot what the smallest information are; and those pictures have been taken from satellites that are orbiting Earth at under 4 hundred miles. The Moon is 250000 miles away. The digital camera became into related to the component to the lunar lander, in a position the place it ought to checklist the ladder and subsequently Armstrong's first step. Later, it became into removed from there by the astronauts and placed atop a tripod to furnish a well-known view of the astronauts' activities. each and every flag introduced by each and every venture became into left there. No lunar touchdown became into achieved in proximity of yet another previous Apollo venture touchdown area.

The landing stage of the lunar lander served/serves as "space launch complex".

After all, you don't need much stuff for a small vehicle, the smallest rockets on Earth use nothing else but a small rail to keep it on course. Some vehicles even don't need a launch complex at all.

As long as your rocket engine is high enough over the surface to not get damaged by kicked up dust, all is fine on the moon. Otherwise, the same rule as on Earth applies: The bigger the rocket, the more equipment you need.

Apart from the above (not forgetting Lunar lander and its hypergolic fuel that will ignite on mixing), to get everything from the Earth to the moon needed the behemoth that was the Saturn V. The Saturn V carried all the fuel required, the command module, the lander and the fuel for the command module and lander fuel and it needed to get this jumble of engineering enough speed up to break earths orbit. That is a lot of fuel and a lot of support and it was in stages.

To get off the moon, no atmosphere, low gravity etc it needed a lot less and they only had to make the command module in orbit around the moon. That command module had the engine to break the far weaker gravity of the moon and send what was left to Earth. Gravity along the way helped.

So, more support to go, a heck of a lot less required to leave.

everyone is batting around that figure.... the Moon has 1/6th the Earth's gravity... well, the Moon has 1/81st the Earth's mass.

While it would take more than a slingshot and a tee-shirt cannon to get back off the Moon into Lunar orbit, it doesn't take a LOT more.

There's the other thing you missed. The Lunar Ascent Module only had to get into Lunar orbit. The Command Module provided the delta v to get back to Earth.

Think of Apollo as climbing a tall tree to get into your tree fort. If you make it to the short rope hanging from the fort, your friends will pull you up the rest of the way. To get back down, all you have to do is climb over the fort's wall and shimmy down the tree trunk.

The lower section (Descent Stage) of the Lunar Excursion Module (LEM) served as a launching pad for the upper crew section (Ascent Stage) which separated from the Descent Stage and contained a small rocket engine so the crew could return to Moon Orbit and link up with the Command Module for the return to Earth.

Watch this footage of the Apollo 17 liftoff from the moon. You can see the rocket engine fire for about one second just as the Ascent Stage lifts off.

http://www.youtube.com/watch?v=Obd_jTO66-0&feature...

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The Moon having approximately 1/6th the gravity of Earth at the surface means the power to lift-off from it's surface requires very little energy,as the further from the surface the module gets,the less gravitational pull it experiences. The initial lift-off firing of the ascent engine is enough to escape the surface,particularly bearing in mind only the upper part of the module takes off,after which the lessening gravitational pull is further reduced by not having an atmosphere to climb through,which reduces drag-factor significantly. Computers will vector the module to the mother-ship for rendezvous...and the superb and intense training of the crews helps a tad if things go pear-shaped. [Apollo 13]

The Lunar Module was the launch site on the moon. The vehicle linked up with the Apollo orbiter at a relatively low altitude. Relight the rockets and use a slingshot orbit and they were on their way back to earth.

No atmosphere, and extremely low gravity on earth. Why do you think you need a giant rocket to launch such a tiny ship from Earth? You could launch from the moon with a tiny rocket, because there is very little resistance.

How do you think Apollo 11 came back?