Reference Terms
from Wikipedia, the free encyclopedia
Dark matter
In astrophysics and cosmology, dark matter is hypothetical matter of unknown composition that does not emit or reflect enough electromagnetic radiation to be observed directly, but whose presence can be inferred from gravitational effects on visible matter.
Note: The above text is excerpted from the Wikipedia article "Dark matter", which has been released under the GNU Free Documentation License.
Related Stories
1
2
Space & Time News
April 15, 2025
Apr. 15, 2025 — Observations of Jupiter show that ammonia is unevenly distributed in the upper atmosphere, against expectations of uniform mixing. Scientists found evidence for a complicated but apparently real process associated with fierce lightning storms: ...
Apr. 15, 2025 — Extreme cosmic events such as colliding black holes or the explosions of stars can cause ripples in spacetime, so-called gravitational waves. Their discovery opened a new window into the universe. To observe them, ultra-precise detectors are ...
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 ...
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 ...
Latest Headlines
updated 12:56 pm ET
Apr. 15, 2025 — First ever supercomputer simulations of Mars with a fully molten core could explain the Red Planet's unusual magnetic field. Billions of years ago, Mars had an active magnetic field. Mysteriously, ...
Apr. 15, 2025 — A new study modeled the chemistry of TOI-270 d, an exoplanet between Earth and Neptune in size, finding evidence that it could be a giant rocky planet shrouded in a thick, hot atmosphere. TOI-270 d ...
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 ...
Apr. 10, 2025 — A new study using functional magnetic resonance imaging (fMRI) reveals the neural mechanisms that contribute to urinary incontinence, a common condition affecting stroke survivors that has a ...
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 ...
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 ...