How come rockets aren't launched into space from on top of a mountain, they would be closer to orbit that way?

Question

Wouldn't 5000 feet above sea level be closer to orbit than from sea level?

Answer 1

Yes, it would. But it would also be more difficult to get equipment and supplies up to the top of that mountain.
The --real-- biggie is being able to launch from the equator to take advantage fo the Earths rotational velocity (a bit over 1000 mph) for getting up to orbital velocity.

Doug

Answer 2

A lot of good info already given. The distance comparison being about the best, especially the logistics of everything. Speed being relative, the equitorial launch does add to the ease of launching only in deep space targets. Where the rocket is going up to obtain orbit around the earth, earth and rocket are spinning along at the same speed at the equator, so relative to each other they are traveling zero miles per hour. To obtain orbit, the rocket must reach escape velocity from earth which is already spinning along with rocket. Orbit is achieved when the rocket's forward speed equals the falling back to earth equals the earth falling away due to being curved, orbit is a controlled fall. Since the rocket and earth move in relation to each other, equatorial speed has no effect on earth orbit items. Headign for the moon or beyond...yes the location of the rocket at launch to maximise the equatorial spin does play a part in the "launch window".


Ah Pegasus....height..yes...speed, the launch vehicle speed is faster in relation to the earth if going east...so maybe...
but the orbit vehicle would launch in relation to mother ship, so equator has no bearing - remember that speed is a relative concept.

Answer 3

Low earth orbit of rocket is about 200km. 5000 feet is about 1.5 km which is insignificant when 200 is considered. Next if rockets are to be in orbit, it is the velocity rather than altitude of launch is important. The velocity being order of few kilometres per sec. If the velocity is more than 7miles per sec the rockets leave from earths gravitational force.

Answer 4

1. It's a question of logistics. How would you get all of the buildings and equipment necessary to launch a rocket up to the top of a mountain? Not to mention the rocket, itself. You can't just put one on the back of a truck, or hang it from a helicopter.

2. Where would you find a mountain top with enough space to build a launch pad and buildings to house safety vehicles and equipment?

3. The fuel savings would not be enough to even begin to justify the expense even if you could satisfy my first two conditions.
.

Answer 5

Putting something into orbit, you gain by launching from a high site, you gain by having an eastward velocity, and you gain by being near the equator. This is all achieved by the "Pegasus" launch vehicle, which is dropped from an airplane travelling eastward along the equator.

Answer 6

true, but the air is too thin and cold to ignite the fuel. Beside the ice build up that would be catastrophic.EDIT: guess some didnt read the question. 5000 feet above sea level.