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

A novel theory suggests that the current expansion rate of the universe is not fixed, but was in fact quite different in the ...

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 ...

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 ...

The universe — everything in existence — is expanding every second! It's only been about a hundred years that humanity has known this, too — that most galaxies are traveling away from us and the ...

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

"Cosmic archaeologists" have discovered an iron-deficient second-generation star, which provides evidence of how ancient stars enriched their successors.

The Big Bang: The moment when the universe — everything in existence — began. ... Right? Turns out, it's not quite that simple. Today, when scientists talk about the Big Bang, they mean a period of ...

Researchers have confirmed three objects spotted with the James Webb Space Telescope in the early universe are galaxies brimming with unexpectedly old stars. Credit: NASA-GSFC / Adriana M. Gutierrez ...

About a century ago, scientists were struggling to reconcile what seemed like a contradiction in Albert Einstein's theory of general relativity. Published in 1915, and already widely accepted ...