how long would it take for a space ship to go from earth to the moon?

Question

any one know ?

Answer 1

Normally, the trip is done in three stages:
1) leave Earth's surface and enter Earth orbit. This could be done in a matter of a few hours. Of course, I am not including the years of preparation and the wait for the perfect time so that the orbit will not need correction.

2) leave Earth's orbit and travel to the Moon in order to enter in an orbit around the Moon. The travel part takes three days with late-20th century rockets. Faster and you increase the risk of missing the very narrow parameters needed to enter a stable Moon orbit (if you miss, you end up in orbit around the Sun, like the first Soviet probes sent towards the Moon).
Slower and it takes forever.
Of course, I am not including the time spent in orbit waiting for the vehicle to be at the right spot, with the right orientation, etc.

3) from an orbit around the Moon to the Moon's surface: a matter of minutes... unless you want to be safe. After all, you may want to hit a precise landing spot where you know that the soil is solid, flat, free of rocks... Also, you want to arrive at an altitude of 0 exactly when the descent and lateral speeds are very close to zero, keeping in mind that you can't use wings or parachutes. You may have to wait in orbit, waiting for the proper position and orientation before breaking orbit.

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Or you can get there much faster by skipping the orbits, like Hergé did in his Tintin books (Objectif Lune & On a marché sur la lune) where the rocket keeps accelerating until the mid-point, turns around, begins decelleration and proceeds directly to "landing" on the Moon (same thing on the way back). In the French version of the books, thee trip takes a little over 4 hours (which makes sense, given the acceleration used throughout the trip).

We do not have the rockets to do that, yet.

Answer 2

That depends. The Apollo missions used a "minimum energy" (also called a Hohmann trajectory). That's the flight trajectory that will get you there with the least expenditure of fuel. It takes about 3-1/2 days to go from Earth orbit to lunar orbit on a Hohmann trajectory (The Hohmann trajectory for Mars takes about 8 to 9 months, by comparision, and can only be sued when the wo planets are in the right positions).

But with a slight increase of speed--just a few hundred mph added t o the minimum speed (about 25,000) you can cut that to about a day and a half. The reason is that the spacecraft slows down a lot at first as Earth's gravity tries to drag it back--bringing the average speed down to about under 3000 mph. But the small extra amount would get you out of the earth's "gravitational well" faster--so you don't slow down as much--and that retained velocity is added to the speed you've added over and above the minimum.

Why didn't the astronauts do this? The reason is that that extra speed requires extra fuel. They were pushing the limits of technology as it was--the added cost and technical challenge just weren't worth the extra cost. That's the same reason unmanned spacecraft also use Hohmann trajectories. We could make them go faster--but then the extra fuel wouldn't leave any room for a payload; either that, or the cost would go up--a lot!

BTW "Hohmann" is the name of the scientist who figured out this type of orbit and showed that it's the most fuel-saving way to get from Earth to the moon or planets.

Answer 3

As you have not defined how fast or slow this theoretical space ship travels then i will say INSTANTLY! as speed would be no object.

Take the good olde star-ship enterprise i believe it can pass the moon in seconds and leave the solar system in less than 60 seconds! now that's great acceleration.

Do i get points for the funniest answer ?

Tetro

Answer 4

So far.. Helios B, the U.S.-German solar probe was the fastest-ever unmanned space probe. Launched in 1976, it was clocked at nearly 42 miles per second (150,000 miles per hour) as it accelerated toward the Sun... Do the math.. about 90 something minutes.. but the "landing" might be a bit rough.. lol

Answer 5

The normal trip of the Apollo program took about three days from launch to moon orbit.

Answer 6

That depends on how fast it can travel. Take the number of miles it can travel in one hour and divide that number into the number of miles between earth and moon. That will give you the number of hours the trip will take.

Answer 7

Missing variables - cannot compute.