Does ultraviolet light come from numerous but faint galaxies or from a smaller number of quasars? The answer may not be too far in the future. A new method developed by researchers at the University College London shows we will soon uncover the origin of ultraviolet light, helping scientists understand how galaxies were built.
The new method builds on a technique already used by astronomers in which quasars act as beacons to understand space. Quasars are the brightest objects in the universe and their intense light is generated by a gas.
The intense light from quasars makes them easy to spot even at extreme distances, up to 95 per cent of the way across the observable universe.
“By studying how this light interacts with hydrogen gas on its journey to earth will reveal the main sources of illumination in the universe,” said cosmologist Dr Andrew Pontzen from UCL.
