Lyman-Alpha Forest Simulations (IMAGE) Scuola Internazionale Superiore di Studi Avanzati Caption Projection of the neutral hydrogen fraction at redshift z=2. Credit The Sherwood Simulation Suite Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.