Everywhere you look, there's a tendency for things to spin. Skaters glide across the ice, and link arms. A soccer ball as it skims across the ground. Water, as it eddies down a channel. Leaves whirl down streets in gusty winds. Colliding cars are prone to spinning after they bounce off each other.
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Spin often occurs when moving bodies come together, and it happens at large scales as much as the small. The Earth and the other planets in our solar system were formed around 4.6 billion years ago when a cloud of dust ''fell'' into itself. The merging bodies were the particles of dust formed from the remnants of earlier stellar explosions. Then shockwaves from a nearby supernova caused the cloud to bunch into a critical mass, kicking off the formation of our solar system.
At the core, the sun began to form, while around the outside, clumps of dust merged into planets, and like our ice skaters, they started to spin. And, like a spinning skater who pulls in their arms, the solar system and its proto-planets began to spin faster.
Without gravity, the Earth would no longer be restrained by the Sun, and would fly off in a straight line, maintaining its current velocity of nearly 30 kilometres per second. At that rate, it'd shoot past the Moon in about 3.5 hours.
The solar system itself is part of a larger spinning mass. It whips around the galactic centre at 200 kilometres per second.
If skaters perform to music, there is also a harmony of the spheres. This ancient idea has more recently been found to have some truth. Bode's Law says that each planet is approximately twice as far from the Sun as the one before.
Predictions made using Bode's Law have been near enough to help astronomers locate planets orbiting around other suns.
Spinning is a remarkably stable form of movement. You can watch carp in the lake twitch their tail, leaving a trail of little vortexes that continue for a surprisingly long while. On a bigger scale, cyclones usually last about a week, but one in 1993 lasted 24 days.
Eventually, all succumb to friction, but in the vacuum of space, there is almost no friction. There is however, some tidal drag, which is why the Moon always faces the same side towards us.
The Earth will continue orbiting the Sun for a very long while. Instead, the Sun will come to us. In about 7.59 billion years it will bloat into a red giant star and the Earth will probably fry.
