Library / English Dictionary |
DARK MATTER
Pronunciation (US): | (GB): |
I. (noun)
Sense 1
Meaning:
(cosmology) a hypothetical form of matter that is believed to make up 90 percent of the universe; it is invisible (does not absorb or emit light) and does not collide with atomic particles but exerts gravitational force
Classified under:
Hypernyms ("dark matter" is a kind of...):
matter (that which has mass and occupies space)
Meronyms (parts of "dark matter"):
weakly interacting massive particle; WIMP (a hypothetical subatomic particle of large mass that interacts weakly with ordinary matter through gravitation; postulated as a constituent of the dark matter of the universe)
Domain category:
cosmogeny; cosmogony; cosmology (the branch of astrophysics that studies the origin and evolution and structure of the universe)
Context examples:
Firstly, most of these early massive galaxies are strongly dominated by normal matter, with dark matter playing a much smaller role than in the Local Universe.
(Dark Matter Less Influential in Galaxies in Early Universe, ESO)
Another way to understand the WISE results involves dark matter.
(NASA's WISE findings poke hole in black hole 'Doughnut' theory, NASA)
Using this method, the team uncovered dark matter clumps along the telescope's line of sight to the quasars, as well as in and around the intervening lensing galaxies.
(Cosmic Magnifying Glasses Find Dark Matter in Small Clumps, NASA)
Apparently it took billions of years longer for dark matter to condense as well, so its dominating effect is only seen on the rotation velocities of galaxy discs today.
(Dark Matter Less Influential in Galaxies in Early Universe, ESO)
Although astronomers cannot see dark matter, they can detect its presence indirectly by measuring how its gravity affects stars and galaxies.
(Cosmic Magnifying Glasses Find Dark Matter in Small Clumps, NASA)
This is in stark contrast to present-day galaxies, where the effects of mysterious dark matter seem to be much greater.
(Dark Matter Less Influential in Galaxies in Early Universe, ESO)
Dark matter is an invisible form of matter that makes up the bulk of the universe's mass and creates the scaffolding upon which galaxies are built.
(Cosmic Magnifying Glasses Find Dark Matter in Small Clumps, NASA)
The presence of dark matter can explain why the outer parts of nearby spiral galaxies rotate more quickly than would be expected if only the normal matter that we can see directly were present.
(Dark Matter Less Influential in Galaxies in Early Universe, ESO)
All galaxies, according to this theory, form and are embedded within clouds of dark matter.
(Cosmic Magnifying Glasses Find Dark Matter in Small Clumps, NASA)
This suggests that 3 to 4 billion years after the Big Bang, the gas in galaxies had already efficiently condensed into flat, rotating discs, while the dark matter halos surrounding them were much larger and more spread out.
(Dark Matter Less Influential in Galaxies in Early Universe, ESO)