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.
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April 14, 2025
Apr. 14, 2025 — Researchers may have answered one of space science's long-running questions -- and it could change our understanding of how life began. Carbon-rich asteroids are abundant in space yet make up less than 5 per cent of meteorites found on ...
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Apr. 2, 2025 — Researchers interrogated the 'sounds' of a cluster of stars within the Milky Way, uncovering a new technique for astrophysicists to probe the universe and learn more about its ...
Latest Headlines
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Apr. 10, 2025 — A team has revealed new insights into the motion of massive stars in the Small Magellanic Cloud (SMC), a small galaxy neighboring the Milky Way. Their findings suggest that the gravitational pull of ...
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Apr. 2, 2025 — World leaders should look to existing international law on the use of force to address the threat of space becoming ever more militarized, a new ...
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