New research suggests that dark matter, the universe's most mysterious "stuff," may actually have been born "hot." If this is ...

The coldest and densest molecular gas clouds in the interstellar medium can have temperatures of 10 K (-505 °F/-263 °C), ...

If dark stars existed, they would have been capable of forming in the universe before ordinary stars could have formed. When ...

If there is an absolute law in the universe, it’s that nothing can travel faster than the speed of light. For science-fiction enthusiasts, that’s a bit depressing. Space is big, and while the speed of ...

Wormholes are often imagined as tunnels through space or time—shortcuts across the universe. But this image rests on a ...

It’s always amazing, and more than a little humbling, when the universe reminds us that our “common sense” is provincial, falling apart on cosmic scales. If you’re on the surface of Earth—and I’m ...

Everything humanity has ever touched, measured, or imagined as “normal” matter is a tiny sliver of reality. Less than 5 percent of the known cosmos is made of the atoms that build stars, smartphones, ...

After a multi-decade-year mission to understand the nature of the universe, a telescope perched in the mountain plateaus of northern Chile said goodbye in 2022. Now, its final data release is ...

Tinkering at their desks with the mathematics of quantum space and time, physicists have discovered a puzzling conundrum. The arcane rules of quantum theory and gravity let them imagine many different ...