A study published recently in Nature has revealed the presence of a hitherto undetected component of the universe—large masses of gas surrounding distant galaxies. An international team from some 10 scientific institutions has shown that almost the whole of the early universe shows a faint glow in the Lyman-alpha line. This line is one of the key “fingerprints” of hydrogen. This detection reveals the existence of extensive masses of gas around primitive galaxies. The results of this study are based on observations made with the MUSE spectrograph on the Very Large Telescope (VLT) of the European Southern Observatory, Cerro Paranal, Chile.