Planet
A planet (from Ancient Greek αστήρ πλανήτης (astēr planētēs), meaning "wandering star") is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals. The term planet is ancient, with ties to history, science, mythology, and religion. The planets were originally seen by many early cultures as divine, or as emissaries of deities. As scientific knowledge advanced, human perception of the planets changed, incorporating a number of disparate objects. In 2006, the International Astronomical Union (IAU) officially adopted a resolution defining planets within the Solar System. This definition has been both praised and criticized, and remains disputed by some scientists since it excludes many objects of planetary mass based on where or what they orbit. While eight of the planetary bodies discovered before 1950 remain "planets" under modern definition, some celestial bodies, such as Ceres, Pallas, Juno, Vesta (each an object in the Solar asteroid belt) and Pluto (the first-discovered trans-Neptunian object), that were once considered planets by the scientific community are no longer viewed as such.
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Famous quotes containing the word planet:
“The planet on which we live is poorly organized, many areas are overpopulated, others are reserved for a few, technology’s potential is only in part realized, and most people are starving.”
—Friedrich Dürrenmatt (1921–1990)
“Everywhere—all over Africa and South America ... you see these suburbs springing up. They represent the optimum of what people want. There’s a certain sort of logic leading towards these immaculate suburbs. And they’re terrifying, because they are the death of the soul.... This is the prison this planet is being turned into.”
—J.G. (James Graham)
“Mad? Is it mad that you destroy other people to save yourselves? You have done this. Is it mad that one country must destroy another to save themselves? You have also done this. How then is it mad that one planet must destroy another who threatens their very existence?”
—Edward D. Wood, Jr. (1922–1978)