Planet

A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young protostar orbited by a protoplanetary disk. Planets grow in this disk by the gradual accumulation of material driven by gravity, a process called accretion. The Solar System has at least eight planets: the terrestrial planets Mercury, Venus, Earth and Mars, and the giant planets Jupiter, Saturn, Uranus and Neptune. These planets each rotate around an axis tilted with respect to its orbital pole. All of them possess an atmosphere, although that of Mercury is tenuous, and some share such features as ice caps, seasons, volcanism, hurricanes, tectonics, and even hydrology. Apart from Venus and Mars, the Solar System planets generate magnetic fields, and all except Venus and Mercury have natural satellites.

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2 Incredibly Rare Exoplanets Could Give Us Insights About a Planet Close to Home

A long-lost rogue planet could explain unexpectedly distant asteroids

New evidence for liquid water on Mars suggests the planet is geothermally active

A Planet-Sized Heatwave Has Been Found in Jupiter's Atmosphere

New evidence for liquid water on Mars suggests the planet is geothermally active

Scientists Identify the Source of the Planet Ceres’ Unexpected Geological Activity

Ingenuity Mars helicopter notches 33rd Red Planet flight

Phosphine is produced by bacteria in the swamps of Earth. For some reason it's also floating around the atmosphere of Venus. 2 years ago this discovery led to skepticism, but after multiple confirmations, 6 spacecraft are now scheduled to visit "the forgotten planet" for the first time in 30 years.

Venus: The scorching second planet from the sun

New Omega Marstimer watch keeps time on Earth and the Red Planet

Heating homes with hydrogen is bad for both your wallet and the planet

Mars is the nearest possibility to have another planet – Exclusive with Apollo 16 astronaut Charles Duke

Jupiter Is the Closest It's Been to Earth in 59 Years—You'll Be Able to See the Planet's Magnificent Stripes Tonight

Planet Venus: 20 interesting facts about the scorching world

This Fall: ‘Fireballs’ From Halley’s Comet, Once-In-A-Lifetime Planet Views And The Best ‘Blood Moon’ Eclipse Until 2029

NASA's Mars lander hears the 'bloop' of meteorites hitting the Red Planet

Mars Is Mighty: First Webb Space Telescope Images of Red Planet

JWST's First Glimpse of Mars Reveals The Red Planet in a New Light

Earth's First Continents Sank Into The Planet Before Rising Up Again

Mars rover nears milestone in ambitious plan to return first rocks from another planet