Reference Terms
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Definition of planet
The definition of "planet" has for some time been the subject of intense debate.
Note: The above text is excerpted from the Wikipedia article "Definition of planet", which has been released under the GNU Free Documentation License.
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Space & Time News
April 12, 2025
Apr. 11, 2025 — Astronomers are investigating the longest and most energetic bursts of X-rays seen from a newly awakened black hole. Watching this strange behavior unfold in real time offers a unique opportunity to learn more about these powerful events and the ...
Apr. 9, 2025 — Astronomers have peered back in time to find what looks like a population of 'hidden' galaxies that could hold the key to unlocking some of the universe's secrets. If their existence is confirmed it would 'effectively break current models of galaxy ...
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 ...
Apr. 2, 2025 — In new images, scientists have gotten the closest look yet at Sagittarius C -- a 'stellar nursery' where clouds of gas and dust have collapsed to form thousands of new ...
Latest Headlines
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Apr. 9, 2025 — The NASA/ESA Solar Orbiter recently recorded the highest-ever concentration of a rare helium isotope (3He) emitted from the Sun. A Southwest Research ...
Apr. 8, 2025 — Every galaxy is thought to form at the center of a dark matter halo. Stars are formed when gravity within dark matter halos draws in gas, but astrophysicists don't know whether star-free dark matter ...
Apr. 7, 2025 — Despite its uniquely rich inventory of organic molecules, Saturn's largest moon, Titan, may be able to support only a minuscule amount of biomass, if life exists on the moon, according to a study ...
Apr. 7, 2025 — What if we spend decades building advanced telescopes to search for life on other planets and come up emptyhanded? A recent study exploring what we can learn about life in the universe -- even if we ...
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 ...
Apr. 4, 2025 — Astronomers have discovered an extremely rare, high mass, compact binary star system only ~150 light years away. These two stars are on a collision course to explode as a type 1a supernova, appearing ...
Apr. 3, 2025 — A solar wind event from 2017 that hit Jupiter and compressed its magnetosphere created a hot region spanning half Jupiter's ...
Apr. 3, 2025 — The same dirt that clings to astronauts' boots may one day keep their lights on. Researchers created solar cells made out of simulated Moon dust. The cells convert sunlight into energy efficiently, ...
Apr. 2, 2025 — For a long time, scientists thought that only actively star-forming galaxies should be observed in the very early Universe. The James Webb space telescope now reveals that galaxies stopped forming ...
Apr. 2, 2025 — Miso is a traditional Japanese condiment made by fermenting cooked soybeans and salt. Researchers successfully made miso on the International Space Station (ISS). They found that the miso smelled and ...