Search results
Results from the WOW.Com Content Network
The definition of the term planet has changed several times since the word was coined by the ancient Greeks. Greek astronomers employed the term ἀστέρες πλανῆται (asteres planetai), 'wandering stars', for star-like objects which apparently moved over the sky.
The International Astronomical Union (IAU) adopted in August 2006 the definition made by uruguayan astronomers Julio Ángel Fernández and Gonzalo Tancredi [1] [2] that stated, that in the Solar System, [3] a planet is a celestial body that: is in orbit around the Sun, has sufficient mass to assume hydrostatic equilibrium (a nearly round shape ...
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 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. [1]
The definition of a planet has been a hot topic ever since a change kicked Pluto out of our planetary lineup in 2006. Now, a group of researchers is proposing a new definition yet again—one with ...
As the definition of planet has evolved, the de facto and de jure definitions of planet have changed over the millennia. As of 2024, there are eight official planets in the Solar System per the International Astronomical Union (IAU), [1] which has also established a definition for exoplanets.
In April 2024, Arizona (where Pluto was first discovered in 1930) passed a law naming Pluto as the official state planet. [83] Researchers on both sides of the debate gathered in August 2008, at the Johns Hopkins University Applied Physics Laboratory for a conference that included back-to-back talks on the IAU definition of a planet. [84]
These are lists of planets.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 whose orbits lie within the orbit of Earth. [nb 1] Mercury and Venus: Inner planet: A planet in the Solar System that have orbits smaller than the asteroid belt. [nb 2] Mercury, Venus, Earth, Mars: Outer planet: A planet in the Solar System beyond the asteroid belt, and hence refers to the gas giants. Jupiter, Saturn, Uranus and Neptune ...