For years, cosmologists have argued over a simple question with an awkward answer: How fast is the universe expanding right ...

For more than two decades, the standard model of cosmology has stood as a reliable guide to the universe. Known as Lambda Cold Dark Matter, or ΛCDM, it weaves together dark energy, dark matter, and ...

Astronomers have long known the universe is expanding—but exactly how fast remains one of the biggest mysteries in cosmology. Different techniques for measuring the Hubble constant stubbornly disagree ...

Astrophysicists have presumed for nearly a century that the universe will just keep expanding for all eternity, driven by an invisible force called dark energy. But new data suggest that this is ...

The James Webb Space Telescope is starting to turn a long‑standing cosmic mystery into something that looks almost tangible. By peering into the earliest galaxies and the crowded hearts of nearby ...