On a clear night, the Milky Way and the Andromeda galaxy look like close neighbors. In space, they really are.

In this visualization, each dot represents a gas parcel with a mass approximately 1,000 times that of the Sun in the simulation of the cosmic Dark Ages. The left and right panels compare the cold and ...

Galaxies are far more than the sum of their stars. Long before stars even formed, dark matter clumped up and drew regular matter together with its gravity, providing the invisible scaffolding upon ...

Dark matter is a difficult subject because, on the one hand, we don’t really know if it even exists at all. On the other hand, many models of the universe rely on it to work. So, when a theory comes ...

Faint hydrogen signals from the cosmic Dark Ages may soon help determine the mass of dark matter particles. Simulations suggest future Moon-based observatories could distinguish between warm and cold ...

Earlier this week, science writer Paul Sutter covered a bold new study that leans toward so‑called “fuzzy” dark matter as the ...

For nearly a century, astronomers have known that the universe is expanding. Most galaxies are carried outward with the flow ...

At the center of our galaxy, there’s a mysterious, diffuse glow given off by gamma rays — powerful radiation usually emitted by high-energy objects such as rapidly rotating or exploding stars. NASA’s ...

Dark energy is responsible for the expansion of the Universe, but its true nature is still a subject of much debate. Computer simulations based on the latest astronomical data enable scientists to ...

Faint radio signals from the early Universe, soon detectable by Moon missions, may reveal how dark matter shaped gas cooling and clumping in the cosmic Dark Ages. Ordinary matter, which makes up the ...