Tiny Galaxy Sends Ionizing Light, Illuminating the Early Universe's Fog

Astronomers using Hubble, with confirmation from the James Webb Space Telescope and the Very Large Telescope, detected ultraviolet light escaping from MXDFz4.4, a tiny but intensely star-forming galaxy about 250 million years after the end of the Epoch of Reionization. The escaping light suggests the galaxy carved channels in its gas, allowing ionizing photons to travel into intergalactic space and helping clear the hydrogen fog that blanketed the early universe. This is one of the clearest glimpses yet of a galaxy from that era contributing to reionization, and it hints that more such galaxies may lie hidden in the deepest space images.