Origin
The Earth formed as part of the birth of the Solar System: what eventually became the solar system initially existed as a large, rotating cloud of dust, rocks, and gas. It was composed of hydrogen and helium produced in the Big Bang, as well as heavier elements ejected by supernovas. As this interstellar dust is inhomogeneous, any asymmetry during gravitational accretion results in the angular momentum of the eventual planet. The current rotation period of the Earth is the result of this initial rotation and other factors, including tidal friction and the hypothetical impact of Theia.
Read more about this topic: Earth's Rotation
Famous quotes containing the word origin:
“In the woods in a winter afternoon one will see as readily the origin of the stained glass window, with which Gothic cathedrals are adorned, in the colors of the western sky seen through the bare and crossing branches of the forest.”
—Ralph Waldo Emerson (1803–1882)
“All good poetry is the spontaneous overflow of powerful feelings: it takes its origin from emotion recollected in tranquillity.”
—William Wordsworth (1770–1850)
“We have got rid of the fetish of the divine right of kings, and that slavery is of divine origin and authority. But the divine right of property has taken its place. The tendency plainly is towards ... “a government of the rich, by the rich, and for the rich.””
—Rutherford Birchard Hayes (1822–1893)