Planet - Wikipedia
WebA 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 - NASA Science
WebThe solar system has eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. There are five officially recognized dwarf planets in our solar system: Ceres, Pluto, Haumea, Makemake, and Eris. The inner, rocky planets are Mercury , …
Planet | Definition, Characteristics, & Facts | Britannica
WebApr 19, 2024 · Planet, broadly, any relatively large natural body that revolves in an orbit around the Sun or around some other star and that is not radiating energy from internal nuclear fusion reactions. There are eight planets orbiting the Sun in the solar system.
All About the Planets | NASA Space Place – NASA Science for Kids
WebJul 17, 2019 · All About the Planets. Our solar system is home to eight amazing planets. Some are small and rocky; others are big and gassy. Some are so hot that metals would melt on the surface. Others are freezing cold. We're learning new things about our neighboring planets all the time. We send spacecraft to take pictures, gather information, …
What is a Planet? - NASA Science
WebA planet is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighborhood around its orbit.
What Is a Planet? | NASA Space Place – NASA Science for Kids
WebMay 6, 2024 · What Is a Planet? The Short Answer: A planet must do three things: it must orbit a star, it must be big enough to have enough gravity to force a spherical shape, and it must be big enough that its gravity cleared away any objects of a similar size near its orbit.
planet - National Geographic Society
WebFeb 1, 2024 · A planet is a large object that orbits a star. To be a planet, an object must be massive enough for gravity to have squeezed it into a spherical, or round, shape,. It must also be large enough for gravity to have swept up any rocky or icy objects from its path, or orbit, around the star.
What is a Planet? | Planets – NASA Solar System Exploration
WebA planet is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.
In Depth | Our Solar System – NASA Solar System Exploration
WebOur solar system consists of our star, the Sun, and everything bound to it by gravity – the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune; dwarf planets such as Pluto; dozens of moons; and millions of asteroids, comets, and meteoroids. Beyond our own solar system, there are more planets than stars in the night sky.
What is a Planet? - NASA Science
WebJun 29, 2015 · What is a planet? The question has been pondered by many since the early Greeks came up with the word "planets." Since then the number of "planets" in our solar system has fluctuated, sometimes numbering as high as 15, before it was determined that some were actually asteroids.
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