Read about "Astronomers Thought the Early Universe Was Full of Hydrogen. Now They’ve Found It." at https://hetdex.org/astronomers-thought-the-early-universe-was-full-of-hydrogen-now-theyve-found-it/
McDonald Observatory
Apr 06, 2026
Astronomers Thought the Early Universe Was Full of Hydrogen. Now They’ve Found It.
Astronomers using data from the Hobby–Eberly Telescope Dark Energy Experiment (HETDEX) have discovered tens of thousands of gigantic hydrogen gas halos, called “Lyman-alpha nebulae,” surrounding galaxies 10 billion to 12 billion years ago.
Credit: Erin Mentuch Cooper (HETDEX), JWST image: NASA, ESA, CSA, STScI.
