Scientists said that the inside of neutron stars might contain a form of ultradense matter not found elsewhere in the cosmos.

But in space, the same-sized cube contains only one or two particles. Space, or outer space, is a vast, near-perfect vacuum largely devoid of matter. This vacuum contains very few particles compared ...

A new study suggests that mysterious “dark dwarfs” could provide crucial insights into the true nature of dark matter.

How is matter different from mass? These and other questions about the deepest levels of physics, answered inside.

"I think it's natural to take a break and wonder whether we are fundamentally thinking about this in the wrong way." ...

Dark matter "lampshades" could slip between Earth and distant stars, causing tiny amounts of dimming that may help explain one of the greatest puzzles in science.

Common Denominator Dark matter, the invisible substance that accounts for over 80 percent of the universe's mass, is not an easy thing to detect. We can see its gravitational pull on visible ...

New data is telling us that Neutron stars may make one of the most popular dark matter candidates.

A new satellite galaxy discovered orbiting the Milky Way is either an incredibly ancient, soon-to-fragment clump of stars or the most dark-matter-dominated dwarf galaxy ever found.

How is matter different from mass? These and other questions about the deepest levels of physics, answered inside.