Simulation - merging galaxies and hydrogen emission

One of the key missions of the NASA/ESA/CSA James Webb Space Telescope is to probe the early Universe. Now, Webb’s unmatched resolution and sensitivity have revealed, for the first time, what lies in the local environment of galaxies in the very early Universe. This has solved one of the most puzzling mysteries in astronomy — why astronomers detect light from hydrogen atoms which should have been entirely blocked by the pristine gas that formed after the Big-Bang. 

These new Webb observations have found small, faint galaxies surrounding the galaxies showing this ‘inexplicable’ hydrogen emission. In conjunction with state-of-the-art simulations of galaxies (a sample of which is highlighted in the video above) in the early Universe, the observations have shown that the chaotic merging of these neighbouring galaxies is the source of this hydrogen emission. This video showcases the studied merging system and the stripping of neutral gas from these objects.

This video was produced by Sergio Martin-Alvarez. The Azahar simulations shown in this video are the result of a collaboration of Stanford University and the University of Cambridge, generated in the Cosma supercomputers from the DIRAC UK HPC facilities.