Silhouettes Of Early Galaxies Reveal Few Seeds For New Stars
An international team of astronomers has discovered that gas around young galaxies is almost barren, devoid of the seeds from which new stars are thought to form—molecules of hydrogen.
Without starlight to see them directly, the team, which includes Dr. Regina Jorgenson of the Institute for Astronomy at the University of Hawaii at Manoa—observed the young galaxies’ outskirts in silhouette.
They searched for telltale signs of hydrogen molecules absorbing the light from background objects called quasars—supermassive black holes sucking in surrounding material—that glow very brightly.
“Previous experiments led us to expect molecules in about 10 of the 90 young galaxies we observed, but we found just one case,” said Associate Professor Michael Murphy from Swinburne University of Technology in Australia. He co-led the study with Jorgenson.