Matter is defined as that which 1) has mass and 2) has volume or takes up space. Mass is an intrinsic property whose base SI unit is the kilogram (kg).

Dark matter is one of nature's most confounding mysteries. It keeps particle physicists up at night and cosmologists glued to ...

Physicists working at the CERN particle physics lab said they detected a slight but significant difference in how particles ...

Invisible dark matter makes up most of the mass in the universe, far outweighing the amount of matter we can see. (Image credit: Dark matter, R. Caputo et al. 2016; background, Axel Mellinger ...

Dark matter, the mysterious form of unobserved matter which could make up 85% of the mass of the known universe, is one of science's biggest manhunts.

With 10 times the mass of the Milky Way, this filamentary structure accounts for much of the universe's "missing matter," the search for which has baffled scientists for decades.