2007-02-23 11:01:49 · 7 answers · asked by Jason432 2 in Science & Mathematics ➔ Astronomy & Space
You have been given the conservation of angular momentum answer by at least two others.
I, however think the rotation is an effect of the electrical charge from the solar wind acting on the earths magnetic field. The solar wind is electrified and earth is like a conductor with a current going past it. This induces a magnetic field on earth. This makes earth rotate like the armature of an electric motor!
The only problem is that this idea and the angular momentum idea both fail to explain planets which rotate with their axes pointing towards the sun. One of the planets in our system does this, it is Uranus. The other truly odd planet as far as rotation is venus which rotates backwards slowly.
I think, in view of this, that nobody knows yet why planets rotate the way they do.
2007-02-23 11:23:59 · answer #1 · answered by U-98 6 · 0⤊ 0⤋
Basically, it started off already turning.
When the giant cloud of dust and gas collapsed to form the solar system, it was already spinning. This rotational energy got transfered to the forming system, resulting in the spin of the Sun, the direction of the planets' orbits and the original spins of the planets.
Thereafter, the spin of each planet was affected by various factors. Inner planets had their spin affected by the Sun's tidal effect: Mercury's spin is harmonic (3 rotation in relation to the stars for 2 orbits around the sun); the slow spin of Venus is also the result of tidal braking (shown by Laskar and Correia a few years ago - abstract at link 1).
Earth is a bit further from the Sun so that the Sun's tidal effect was less on Earth than on Venus.
Otherwise, all planets orbit the sun in the same direction as the Sun's rotation and almost all planets rotate on their axis in the same direction, as their orbit, except Venus and Uranus.
Venus was explained.
Uranus is spinning on its side and there is, as yet, no complete explanation.
So, whatever caused the spin had to be all-encompassing. The collapsing cloud that formed the solar system seems to be it.
2007-02-23 19:15:49 · answer #2 · answered by Raymond 7 · 2⤊ 0⤋
Momentum. It is thought that the earth and other planets were formed from a spinning cloud of gas. The angular momentum of the gas was preserved in the spinning of the planets.
The tidal effects of the moon and sun are actually slowing down the Earth, but the effect is negligible in human timescales.
2007-02-23 19:06:17 · answer #3 · answered by davidbgreensmith 4 · 0⤊ 0⤋
It is just "coasting" on the momentum left over from its formation billions of years ago. Since there is almost no friction in space, it can go on for billions of years without any energy source.
2007-02-23 19:11:55 · answer #4 · answered by campbelp2002 7 · 0⤊ 0⤋
THE EARTH DOES NOT SPIN ON IT'S AXIS..IT WOBBLES.
GRAVITY AND VIBRATION ARE THE CAUSE OF MOTION PERIOD.. IT'S MORE LIKE A MERRY-GO-ROUND
2007-02-23 19:09:17 · answer #5 · answered by ? 1 · 0⤊ 0⤋
Conservation of angular momentum.
2007-02-23 19:04:57 · answer #6 · answered by Anonymous · 0⤊ 0⤋
Objects resist change in their motion (Inertia.)
2007-02-23 22:45:28 · answer #7 · answered by chase 3 · 0⤊ 0⤋