What causes the earth to spin on its axis?

Answer 1

Best Answer - Chosen by Voters

It is far more likely that something will be spinning when it condenses. That is why the earth started spinning. Since there is so little friction in space, there is very little causing the spin to slow down. It *does* slow down over time. Because of this, there were over 400 days in a year a couple hundred million years ago.

Answer 2

Ask O'reilly!

Answer 3

i think its gravity form the sun

Answer 4

Sorry i thought the world was on the back of ATLAS

Answer 5

There's controversy regarding this subject. Some scientists claim proto-planetary accretion, some claim solar tidal forces, some claim hemispheric cooling. The way accretion is explained is where particles/mass is coalesced onto the planets surface. Mass entering the orbit of the planet strikes the surface at a tangent or near tangent, causing spin. During the formation of celestial bodies, matter is strewn about by shock waves and these "waves" are what causes the spinning of planets. the waves may hit the planets at off-axis, causing them to spin.
The other theory is where planets cooling after their formation are subjected to heating on the solar side. this heating and cooling of hemishperes causes them to spin much like a Crooke's radiometer.
The reason why we are still spinning is the law of conservation where a body in motion remains in motion, unless acted...blah,blah...

Source(s):

http://adsabs.harvard.edu/abs/1989Icar..…
http://www.springerlink.com/content/j806…
http://en.wikipedia.org/wiki/Crookes_rad…

Answer 6

Gravity is required (thank you Surveyor) and momentum ( I would call this inertia.
It also requires magnetic fields, believe it or not - which keeps the earth the right way up and make it spin around the same way all of the time.

Answer 7

Think of water spinning down a plughole....now imagine the matter which came together to form the Earth spiralling down tawards a gravitational centre.

You got spin.

Answer 8

Momentum like a gyroscope.

Answer 9

The moon causes the earth to spin on its axis, if the moon was not there the earth would wobble on its axis and cause huge damage to life on earth.

Answer 10

gravity!!!!!!!!!

Answer 11

I didn't do it!!! I was on holiday when it happened!!

LOL!!

Answer 12

Gravitational pull

Answer 13

magic dust

Answer 14

A lot of Harlem Globetrotters.

Answer 15

Because of a number of reasons, the main one, our Earth is not a perfect sphere. Secondly, the mass and density of the sun is not absolutely perfect. Hence, the space distortion caused by the Sun is not symetrical, therefore an imperfect gravitational force on the earth mass.

Getting back to the 1st reason, the oval shape of the Earth and the gravitational pull of the sun, and the sun's velocity within the Milky Way, all sum up to cause a spinning mass.

And thirdly, the initial inertial energy during the formation of the solar system was random and, like a curve ball pitcher, the thrust was off-center. The odds of a thrust that was dead-center is astonomical. The odds of missing other large asteroids is also astronomically large.

The only time an object would not spin if the initial thrust was dead center, there were no objects to interfere with its path, the object was absolutely circular and the sun gravitional force was even. Lacking the above, we'll always be spinning.

Then there's the "core is a molten mass locked in a vault" answer. As the gravity of the sun pulls on the earth, combined with the forward momentum of the earth, we establish a revolution of the planet. The fact that the earth has an active seismic body means that our liquid core has gravity act on it. Just like the revolution, the dynamic of forward momentum and solar gravity causes the planet to wobble, or rotate. The fact that is does so at the magnetic poles is due to electron discharge that makes the magnetosphere as well as defines the poles.

Answer 16

Angular momentum, look it up...

Answer 17

The Earth, Sun and planets condensed out of a nebula ( cloud) of gas and dust, which was in turn rotating around the galactic centre. Its own rotation, at first, was very slow, but, as the early nebula condensed, the speed of rotation increased - This is just like the case of a ballet dancer whose rotation speed increases as she draws in her hands from an outstretched to a "by your sides" position as she spins . This is the principle of conservation of angular momentum.
It continues to this day because the Earth being very heavy, has
enormous momentum, and, Space being effectively a vacuum, offers no resistance. However there is evidence that, over geological time, the Earth's day has grown longer- it was less than 21 hours when the first land animals appeared, and at formation was about 4 hours. One day it will be 47 hours. One factor slowing down the Earth's rotation is the presence of the Moon, whose gravitational pull provides a small resistance. The Moon , being much lighter, has slowed into lockstep with Earth so that its day equals its orbital period ( a month).
:-)

Answer 18

There are two, possibly three important pieces to that puzzle. First, we commonly assume that the earth coalesced during the early solar system's broader accretion disk. The bulk collapsed into the main body, our sun. At various points smaller collections were made and those are the planets. Each was an accretion disk area, sweeping its unique piece of space (part of the new definition of a planet, and part of what causes Pluto to be excluded from the planetary list). So the angular momentum of the mass spiraling down upon the center of gravity of the body is what gave it its initial spin.

A second aspect, according to some notions, is that two centers of gravity were somehow formed and the instability is what caused a rift and the moon was spun off. Still in a hot and molten form from the energies of accumulation, and perhaps a fair flash of energy from the sun when it was new, and these hot bodies then spherically formed around their own centers of gravity, a surface crust forming as they cooled.

A possible third aspect that has been given some thought from time to time, admittedly often very little thought but present in discussions nonetheless, is that a planet or such massive body swept by the earth at some very ancient time. Often, that discussion is part of what supposedly brought about the moon, a shattering blow in some billard-ball type action in the early solar system, and that supposedly gave or assisted our planet's spin.

One thing that contributes even today is the moon orbiting our globe. The center of gravity, or barycenter, of the earth and the moon is off-center to the earth's center of mass. This almost mechanically assists in the earth's turn, although there would be some argument over whether this pushes or pulls the cycle along. Next time you look at a bicycle with its two different size major gears, one large and one small, think about this, okay?

Answer 19

Every so often the Chinese all run in one direction to turn it round

Answer 20

I see hamsters

Answer 21

conservation of anguler momentum

Answer 22

It was spinning when it was formed and it carries on spinning as there is nothing to stop it.

Answer 23

the moon doesn't spin in relation to the earth which is weird.. i would have thought the earth spins because it's got a heavy side.. inertia would do the rest.... it's all relative of course but v. good question...

Answer 24

The world sits on the back of Atlas, but Atlas does not move.

Atlas however stands on the back of the Great Cosmic Turtle.

The Great Cosmic Turtle actually moves through the heavens and causes the Earth to rotate.

Answer 25

Momentum. The previous 2 answers are actually funny... but wrong. The original spin may have been caused by some kind of asteroid impact, but momentum is what keeps it spinning.