Reference Terms
from Wikipedia, the free encyclopedia
Planet
The International Astronomical Union defines "planet" as a celestial body that, within the Solar System that is in orbit around the Sun; has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape; and has cleared the neighbourhood around its orbit; or within another system, it is in orbit around a star or stellar remnants; has a mass below the limiting mass for thermonuclear fusion of deuterium; and is above the minimum mass/size requirement for planetary status in the Solar System.
Note: The above text is excerpted from the Wikipedia article "Planet", which has been released under the GNU Free Documentation License.
Related Stories
1
2
Space & Time News
June 8, 2024
May 31, 2024 — Mars has a distinct structure in its mantle and crust with discernible reservoirs, and this is known thanks to meteorites that scientists have analyzed. These results are important for understanding not only how Mars formed and evolved, but also for ...
May 23, 2024 — Researchers have now seen the formation of three of the earliest galaxies in the universe, more than 13 billion years ago. The sensational discovery contributes important knowledge about the ...
May 23, 2024 — The first scientific pictures from the Euclid satellite mission have revealed more than 1,500 billion orphan stars scattered throughout the Perseus cluster of ...
May 23, 2024 — While thousands of planets have been discovered around other stars, relatively little is known about them. A NASA catalog featuring 126 exotic, newly discovered worlds includes detailed measurements that allow for comparisons with our own solar ...
Latest Headlines
updated 12:56 pm ET
June 7, 2024 — Researchers have discovered that the turbulence found in the thermosphere -- known as the gateway to space -- and turbulence in the troposphere, here closer to sea level, follow the same physical ...
June 7, 2024 — Researchers have provided a simple and comprehensive -- if less dramatic -- explanation for bright radar reflections initially interpreted as liquid water beneath the ice cap on Mars' south ...
June 5, 2024 — New partitioning coefficients of first-transition row elements, Ga and Ge between olivine and silicate melt have been reported. New high-temperature experiments have investigated the effects of ...
June 6, 2024 — Research reveals a shocking discovery about the history of our universe: the Milky Way Galaxy's last major collision occurred billions of years later than previously ...
June 6, 2024 — In the first quintillionth of a second, the universe may have sprouted microscopic black holes with enormous amounts of nuclear charge, MIT physicists propose. The gravitational pull from these tiny, ...
June 6, 2024 — Using the James Webb Space Telescope, a team of astronomers studied the properties of a planet-forming disk around a young and very low-mass star. The results reveal the richest hydrocarbon ...
June 5, 2024 — Scientists have detected what they believe to be a neutron star spinning at an unprecedentedly slow rate -- slower than any of the more than 3,000 ...
June 5, 2024 — A groundbreaking method of detecting high-frequency gravitational waves (HFGWs) has been proposed. The team's innovative approach may enable the ...
June 5, 2024 — A rare exoplanet that should have been stripped down to bare rock by its nearby host star's intense radiation somehow grew a puffy atmosphere instead ...
June 3, 2024 — Researchers call for strengthening existing planetary protection policies beyond the space surrounding Earth to include requirements for preserving ...