The James Webb Space Telescope (JWST) has discovered that nearly all of the universe's earliest galaxies were filled with dazzling gas clouds that blazed brighter than the emerging stars within them — and it could help solve a mystery that threatens to break cosmology.
Forming as early as 500 million years after the Big Bang, some early galaxies have been seen glowing so brightly that they shouldn't exist: Brightnesses of their magnitude should come only from massive galaxies with as many stars as the Milky Way, yet the galaxies took shape in a fraction of the time our galaxy took to form.
