Astronomers tallying up all the normal matter—stars, galaxies and gas—in the universe today have come up embarrassingly short ...

Astronomers raised hopes that humanity might not be alone in the universe by announcing on Thursday they have detected the ...

In simplest terms, the rate at which the universe expands on paper doesn’t match actual astronomical observations. That speed ...

"We've always known that we need something to complete the puzzle, but we haven't really known what shape or form those ...

Despite decades of searching for this signal, astronomers have yet to find it. The problem is that our Earth is too noisy, making it nearly impossible to capture this whisper. The solution is to go to ...

Astronomers may have found the long-missing half of the universe's regular matter—and it appears to have been right under our ...

A faint cosmic spin – one rotation per 500 billion years – could resolve the stubborn Hubble tension by tweaking standard ...

Physicist Richard Lieu first explored the idea that gravity could exist without mass—now he’s got a new cosmological model ...

Astronomers may have uncovered a hidden population of galaxies that could rewrite what we know about the universe's evolution ...

Scientists have discovered where Earth's water comes from, and say that it wasn't brought to the planet by asteroid impacts ...