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).

How do you weigh one of the largest objects in the entire universe? Very carefully, according to new research.

For nearly a century, scientists around the world have been searching for dark matter—an invisible substance believed to make ...

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

Researchers may have found our galaxy's missing companions, further bolstering science's most widely accepted cosmological ...

NASA's James Webb Space Telescope (JWST) has produced a new image of the Bullet Cluster, which is a titanic collision between ...

Along with dark matter, there’s a separate entity — making up even more of the mass of the universe — called dark energy. Although shrouded in mystery, dark energy makes up around 68 percent ...

A stock image of a galaxy. A physicist has a new theory that could lessen the need for dark matter to exist. Getty Images/Ellen11. Lieu suggests that the additional gravity needed to hold a galaxy ...

But axions were pushed aside as the WIMPs hypothesis gained more steam. Back-of-the-envelope calculations showed that the ...

For ordinary matter, momentum is given by the formula P = mv, where P is momentum, m is mass, and v is velocity. Even tiny amounts of matter can have vast amounts of momentum if the matter is ...