How does the moon spin around the earth and never fall into it?

Answer 1

Moons orbit their planets, and they maintain stable orbits through gravity and their own orbital velocities. The moon is moving away from the earth at a very slow rate due to tidal effects. This will not be observable for centuries, at least. So it is clear that the moon will not collide with the earth. And everything in the earth-moon system's planetary path has long ago collided with the earth or moon, or left our general neighborhood for wider or narrower orbits. This does not exclude the possibility that objects moving from other parts of space might from time to time collide with us.

Answer 2

The moon is constantly falling toward the Earth. But it's also moving "sideways",

fast enough so that the shape of the Earth curves down just as fast as the

moon falls.

Answer 3

Here's one convenient way to think about things that stay in orbit:

If the moon, or any satellite, had been just hung out there and released, it would

be drawn to earth by the pair of mutual gravitational forces between them, and

there would eventually be a big splash.

But a satellite is not just hung out there. It's also given some speed 'sideways'

(a tangential component). So now, here's what happens ...

-- The satellite is attracted to Earth by gravity, and starts to fall. After a short time,

it has fallen 1 foot toward the center.

-- But ... it also has some speed sideways. So in that same short time, it moved

far enough sideways to where the earth's surface curved 1 foot down! So it's

still the same distance from the Earth as it was before it fell 1 foot down.

-- And now the whole thing starts again.

This works as long as the satellite can keep that sideways motion going. There's

no force acting to take away the sideways motion ... gravity is only pulling down,

not sideways ... and it's not plowing through any substance out in space, so the

sideways motion continues.

If it gets too close to Earth, then there's air molecules out there (atmosphere),

and little by little, they start to act against some of that sideways motion until,

eventually, the Earth's surface no longer falls away as fast as the satellite falls,

and that's the end of the satellite.

The International Space Station is orbiting at an average altitude of about

220 miles (355 km) above the surface. There's almost no atmosphere there ...

but only 'almost', not entirely zero. Between June 2010 and July 2011, the ISS

lost some altitude, and then used some thruster fuel to re-boost itself to the

altitude they wanted to be at, on 19 occasions.

Answer 4

As a matter of fact, the moon is falling. But at the same time, it also has

enough speed 'sideways' so that the surface of the Earth is curving away

from it just as fast as it's falling.

And the reason it doesn't fly off into space is the gravitational forces that

attract the Earth and the Moon toward each other.

In a kind of messy, intuitive way, that's a handy way to understand

gravitational orbits.

Answer 5

Because another planet whose mass is bigger than the Earth's thus having a stronger power of gravity, counterbalance or "neutralize" Earth's power of gravity, so the Moon remains rotating around the Earth and it isn't pulled towards us.

A more orthodox answer:

All of the Earth's "gravitational pull" is required just to keep the Moon in orbit. There's nothing "left over" to pull the Moon into the Earth. If the Earth's gravity were suddenly to disappear,the Moon's inertia would carry it away from the Earth, at a tangent to its orbital path.

The Quaternion Answer.

The Moon stays in orbit because of its Momentum Energy cP, the Dark Energy. The centrifugal force holding the moon in orbit is cDel.P = -cp/r cos(PR).

The gravitational centripetal force is mv2/r = vp/r.

To stay in orbit, Continuity Condition, vp/r -cp/r cos(PR)=0 and v/c=cos(PR). This v/c is the red shift of the moon.

The red shift is an indication of Continuity, Stable orbit, not expansion. The red shift is a marker of the Centrifugal force and the Momentum Energy cP, or the so-called "Dark Energy".

The Energy of the Moon is W = -mGE/r + cmV, a Quaternion Energy.

That was a great explanation. Would the inquirer understand all those advanced equations? Or would him prefer a single answer....(Just to get a simple perception of that matter)(JW70)

Answer 6

The Moon is kept in orbit, because of Earth's gravity.

Answer 7

A Combination of speed and gravity allow the Moon to stay in orbit of the Earth. The moon, however, is slowly moving away from the Earth each year.