The local universe may be expanding more slowly than previously thought, a discovery that could relieve a pesky discrepancy ...

Light released by a distant star does not simply wink out after crossing some threshold of space. In a vacuum, photons keep moving indefinitely, and astronomers routinely detect light that has ...

Cosmic voids may seem like the emptiest places in the universe, stripped of matter, radiation, and even dark matter. But they’re far from nothing. Even in these vast empty regions, the fundamental ...

Observations show the universe appears flat, yet its true size and global shape beyond the observable horizon may remain ...

Ripples in the fabric of space-time called gravitational waves may be the key to solving the Hubble tension — one of the ...

Astronomers have tracked a powerful blast of radiation back to its source, finding a neutron star collision within colliding ...

Now physicists from the University of Washington are taking a big swing at answering that question. All matter exerts gravitational force. The more mass the object has, the greater the force. Yet, a ...

A team of researchers proposes a new vision of the Universe's first moments. Their model eliminates the need for traditional speculative hypotheses. Cosmologists have long worked with the inflation ...

Wormholes are often imagined as tunnels through space or time—shortcuts across the universe. But this image rests on a misunderstanding of work by physicists Albert Einstein and Nathan Rosen. In 1935, ...

There’s endless debate among cosmologists about what really makes up the emptiness of outer space, though many believe that mysterious stuff that we now call dark matter and dark energy represent a ...

A NASA team using the Hubble Space Telescope found an object in space never recorded before, nicknamed “Cloud-9.” Cloud-9 is a starless, gas-rich, dark-matter cloud considered a “relic” or remnant of ...