Is moon moving away from earth.....?

Question

plz give with proof...

Answer 1

Astronomers will tell you the moon is moving away from the Earth and provide elaborate proof that the tides on Earth cause this. But, think about it rather than accept this stuff. After all the moon and Earth are locked in a common orbit around the sun so where can the moon go? The theory of the moon is very old and not at all logical even if math can be used to make a very strong case it is logical. I think most people(astronomers) just accept the common belief because no points are gained in objecting whereas being out of step is bad form or worse.

Answer 2

I have no proof but I heard it on History channel that it is moving away by making outward spirals.

Answer 3

No it will never fly away from earth becose moon is in balance of earth gravity and gravity of sun

Answer 4

Yes, the Moon's orbit is slowly retracting away from the Earth. I don't know the necessary equations to prove it, but you can easily look it up on the Internet, it's been known for some time that this is occurring.

Answer 5

Every month, the moon moves from a distance of about 363,104 km to a distance of about 405,696 km, and back again.   On top of this, there is a long-term trend of moving away by about 3.8 meters per century.  This is all figured out by looking at the moon with high-precision telescopes, and especially by using laser lights to look at the mirrors that the astronauts left on the moon when they visited.

Answer 6

The Moon is moving away from Earth.

PROOF: Scientists noticed the moon has been moving father away from us. They also noticed that the Moon, today is more further away than it was in the 1960's.

Answer 7

Yes, by a little less than 4 cm per year.  Sorry to the last answerer, but not only the math proves it.  Laser reflectors placed on the Moon confirm it also.  Some time in the future ( a long way off) we will no longer see full solar eclipses, only annular ones, as the Moon's apparant size will be too small to cover the Sun entirely.

Answer 8

Yes it is moving away a few cm per year-- how do we know? We use this device left on the surface of the moon by Neil Armstrong-- to measure the distance with a laser beam--

http://science.nasa.gov/headlines/y2004/...

This is actually ABSOLUTE PROOF that we landed on the moon. I use it every time someone posts a moon-landing hoax question.

Answer 9

I am not sure.  If it is moving away or moving toward then I suppose that is utilized to as evidence for certain theories for the creation of the moon so you may want to check there.  I write mainly to critique an above answer which stated, in essence, "moving away.  Proof: scientists say it is moving away."

Answer 10

Yes. The reason has to do with the earth's tides.

Since the earth rotates faster (24 hr) than it take the moon to orbit the earth (28 days), high tide does not actually occur directly under the moon--it actually advances a bit ahead because the earth is rotating so fast.  The extra mass of the high tide actually pulls the moon forward a tiny bit, giving it some extra energy, and if you give an orbiting object more energy it actually moves farther away and goes slower (which is counter-intuitive, but true).

Of course, this extra energy doesn't come out of thin air--it comes out of the earth's rotational energy, so the earth rotates slower.  Eventually, there will come a time when the earth's rotation and the moon's orbit will have the same period, something on the order of 30-40 days.

This is an inevitable occurrence with all planets or planetoids that have large moons, but the only other known example is Pluto and Charon, so it's interesting that this has not happened for the Earth and Moon yet, which essentially disproves the theory that the Moon formed from the same cloud as the earth (co-accretion).  Presumably, only capture of the Moon or a cataclysmic, high-energy event would result in the Moon's orbit and an Earth day having different periods.

Answer 11

3.8 cm per year (on average)

It is actually found by calculations (already known over fifty years ago).

The Moon causes ocean tides.  The Earth rotates under the tidal bulge, causing friction between the bulge and the ocean bottom (mostly in shallow portions, like the Irish Sea).

The lunar share of the tidal bulge is therefore displaced to the East of where it should be (because of Earth's rotation) by an amount that can be measured -- comparing actual tide times with theoretical tide times without friction.

From this difference, one can calculate the amount of energy "spent" by Earth.  The original calculation was done by Sir Harold Jeffreys in 1952.

Tidal-braking energy due to the Moon is a bit more than 1,000,000,000,000 W -- a million million watts.  (There is also tidal braking due to the Sun).

(a million million is called a trillion in the US and a billion in most other countries).

This energy is taken from Earth's rotational energy:  our day is getting longer by one second every 40,000 years.

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From the Moon's point of view:  The bulge that is directly "under" the Moon is actually to the East.  That is a lot of water (lots of mass).  This means that the field of gravity holding the Moon on its orbit is ever-so-slightly deformed.  This causes a tiny additional pull (towards the East = "ahead" in the direction of Moon's orbit), causing the Moon to seek a higher-energy orbit (meaning: higher).

This is what causes the Moon to recede slowly.

Because the Earth-Moon system is... a system, the amount of energy lost to "tidal braking" by Earth must be equal to the amount of orbital energy gained by the Moon from the gravitational effect of the tidal bulge.  (It is a complicated example of Newton's: for each action there is an equal but opposite reaction).

Therefore, using the energy found from the tide delay calculations, scientist were able to calculate the rate at which the Moon recedes.

3.8 cm per year (1.5 inches).

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As the Moon moves away, the tidal force will diminish.

As the Earth slows down, tidal friction will diminish.

The rates will diminish with time.

Still, if we could wait long enough, the Earth and Moon system would finally reach an equilibrium where the rate of rotation of Earth (a day) would be equal to the orbital period of the Moon (a month).  An Earth day and a month will have the same length (960 of our present hours = 40 days as we now count them).

However, our Sun will go through its red giant phase, in 5 billion years, well before the equilibrium is reached.

If the Earth-Moon system survives that "event" and do reach the equilibrium position, this equilibrium will not be permanent.  There will still be a solar tide (from the white dwarf left behind after the red giant phase) and this will cause the Moon's orbit to get ever-so-slightly smaller with time (so that the "month" will become shorter than the "day").

Therefore, the Moon will never escape Earth.

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The lunar laser-ranging experiments are not quite accurate enough to track this on a year to year basis (4 cm is very close to the accuracy limit of the experiment).  Also, the Moon's orbit is affected by so many things (e.g., the orbit itself is subject to the Sun's tidal effect) that it would take decades of measurements to "prove" the accuracy of the 4 cm per year "prediction".

The best proof comes from archeological biology.  Some mollusks have shells that grow a new layer every day, with the thickness (and nature) of the daily layer being affected by the state of the tide that day (combination lunar and solar tide) and the season (water temperature).  This allows us to guess at the length of day, month and year, at various times in the past.

900 million years ago, the Earth year was made of 480 days of 18 hours each.

(Observer's Handbook 2008, Royal Astronomical Society of Canada)

Answer 12

The Moon is now believed to have been created in the Giant Impact. This happened about 4 billion years ago when a Mars-sized planetoid crashed into Earth. So the Moon has been moving away from Earth ever since it's creation. Today, the rate is about 1 1/2 inches per year. In about 1 billion years, it will stop moving away and the Moon and Earth will be gravitationally and tidally locked. Just as today we see one side of the Moon, in another billion years, the Earth will also show only one side to the Moon. This is common among orbs which are close to each other.

Answer 13

It is moving away from Earth at the rate of 4 cm per year. Not really that fast to notice.

It was already proposed to happen because Earth and moon are tidal locked together - the moon rotates as fast as one orbit takes around Earth (because of the "tides" caused by Earth on the moon) and also the moon causes tides on Earth, slowing Earths rotation down very slowly, which in turn is meaning an exchange of momentum - for slowing Earth down, the moon has to become faster, and when the moon gets faster, the distance to Earth grows by astrodynamic principles.

To verify this prediction, the USA installed special mirrors on the during the Apollo missions to use lasers on Earth for measuring the distance to the moon at millimeter accuracy. The mirrors are still there and are still used for measuring the distance.