Bubble-blowing galaxies could help solve a cosmic mystery
A trio of galaxies has been caught ionizing hydrogen 680 million years after the Big Bang

Bubbles of ionized hydrogen surround three galaxies (illustrated) in the very early universe, perhaps providing a peek into how most of the hydrogen in the cosmos became ionized.
V. Tilvi et al/arXiv.org 2020, NSF’s Optical-Infrared Astronomy Research Lab, KPNO, AURA