Why can a rocket land on the Moon, but not land back on Earth?

Answer 1

The moon has several things going for it first there is less gravity, second things don't burn up in the atmosphere if they move too fast on the moon so you only need to slow down just before you land using much less fuel. Third you leave everything you don't need on the moon so that you don't need a lot fo fuel to escape the moon gravity when time to leave comes. Fourth the skin on a lunar landed was basically as thick as a few sheets of aluminum foil, to keep the weight down.

On the earth you have roughly 6 times the gravity requiring much more fuel, you must slow down before entering the atmosphere, which results in a much longer fuel burn to keep the craft coming in slowly. The structure would have to be considerably heavier to handle the rigors landing of earth.

It's no mystery why rockets have stages and the shuttle loses it rocket boosters and fuel tank, once they are out of fuel they are nothing but dead weight, and a serious, almost impossible to overcome, impediment to escaping the Earths atmosphere. If you add the fuel load needed to land under power on Earth you would never be able to get out of the Earths gravity.

Nothing coming back from space lands under power, even NASA's shuttles don't land under power. They are basically the world largest and heaviest flying brick, impersonating a glider, when they land.

Now if you just want a rocket to land on the earth it can be done but you aren't going to make it in outer space first. And as mentioned before the Earths atmosphere make landing and recovery by other methods cheaper, safer, and much more practical.

Answer 2

The earth's gravity is 6 times stronger than the moon's. So at least 6 times more fuel is needed. Also rockets have not landed on the moon. The moon landers used by the Apollo program were just a very small part of the large Saturn rocket.

Answer 3

Rockets didn't land on the moon. The moon lander, a relatively small unit compared to the multi-stage Saturn V rocket landed on the moon. The lower section was left behind and the command capsule returned to earth. I would guess the lower section was left behind because it wasn't needed for anything on the voyage back, and why drag extra mass back for no reason? it's a very long trip.

Back to the rocket, to make it simple, each stage carried fuel for a different part of the escape and voyage. As the section's fuel was used up that section was jettisoned, thus only a very small part of the massive rocket actually reached the moon.

Answer 4

A rocket never landed on the moon. And when we use rockets to launch into space, they are burned up and destroyed.
We probably have or will have by the next moon landing the technology to launch from earth,arive on the moon,then use the same vehicle to safely return to earth in.

Answer 5

Gravity and fuel. The shuttle uses several million pounds of fuel just to generate enough thrust (1.2 million pounds) to overcome gravity and get into orbit.

Apart from a small reserve for manoeuvring and re-entry, all the fuel contained within the shuttle, the SRBs and the main tank is expended by the time it reaches orbit.

When the shuttle re-enters the atmosphere, it is completely unpowered - which is why astronauts have nicknamed it "The Flying Brick"

Therefore, for a re-usable vehicle to get to the moon, land, take off again and return to earth in a similar manner to the shuttle, it would require more fuel - more fuel equals more weight which equals more fuel needed to lift the extra weight and so on and so forth.

You see the problem?

Answer 6

There's only 1/6 earth's gravity on the moon so it takes much less fuel plus the moon has no atmosphere so the rocket doesn't need to slow down high up to avoid burning in the atmosphere. The shuttle does if you considedr that a rocket.

Answer 7

It can. But we do not use that technology, for cost and logistical reasons. On the moon, there is no air, so we cannot have a space-shuttle like landing. Space-shuttle landing is much cheaper than rockets and requires much less fuel.

Answer 8

They can, but usually don't bother because the air makes wings and parachutes a better idea. But see the source for some rocket landings on Earth.

Answer 9

the moon has a lot less gravity and not atmosphere then the earth, a lot less energy is required to get into space from the moon meaning you don't need as much fuel. all the stuff you see come off of the shuttle as it goes into space, that's just so that it can get out of earths gravity well.

Answer 10

I THINK it can be done.
but why waste the fuel,
when they went to the moon in the 60's & 70's they landed and then took off, but what was the point of bring, that module back when they had the orbiting craft to land back on earth.