In the vast universe, galaxies rotate in ways that don’t make sense if only visible matter is considered. For almost a ...

If this scenario plays out, “the world as we know it would collapse like a house of cards,” says one theoretical physicist.

If dark energy is weakening, it stands to reason that eventually gravity will become dominant and the universe will begin to ...

Every galaxy we can see is believed to sit at the center of a huge cloud of invisible material called a dark matter halo. These halos stretch far beyond the edges of the visible stars and gas in a ...

A new theory challenges the standard model of cosmology, arguing that dark matter and dark energy are not the forces behind cosmic expansion.

Learn how through a process known as molecular hydrogen cooling, stars may be able to form in dark matter halos under 10 ...

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 ...

First discovered in the 1990s, dark energy has come to feel like a familiar face of the cosmos. Astronomers first imagined this unseen entity as a constant presence that has, since the beginning, ...