Planet
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A planet is a large, rounded astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself. The Solar System has eight planets by th
The eight planets of the Solar System with size to scale (up to down, left to right): Saturn, Jupiter, Uranus, Neptune (outer planets), Earth, Venus, Mars, and Mercury (inner planets)
A protoplanetary disk
Protoplanets colliding during planet formation
Earth's atmosphere
Saturn
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Saturn is the sixth planet from the Sun and the second largest in the Solar System, after Jupiter. It is a gas giant, with an average radius of about 9 times that of Earth. It has an eighth of the ave
Planet
…eight planets by the most restrictive definition of the term: the terrestrial planets Mercury, Venus, Earth, and Mars, and the giant planets Jupiter, Saturn, Uranus, and Neptune. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out…
A global storm girdles the planet in 2011. The storm passes around the planet, such that the storm's head (bright area) passes its tail.
Saturn's north polar hexagon as imaged by the Cassini spacecraft.
Auroral lights at Saturn's north pole
An amateur telescopic view of Saturn