An article published in the journal “Nature” reports a study on the Milky Way’s formation that provides evidence that the part known as the thick disc started forming about 13 billion years ago, 2 billion earlier than previously thought. Maosheng Xiang and Hans-Walter Rix of the Max-Planck Institute for Astronomy, Heidelberg, Germany, used data collected by ESA’s Gaia space probe and observations conducted with the LAMOST telescope to reconstruct the Milky Way’s formation and evolution phases. In particular, the researchers focused on the period between 13 and 8 billion years ago, when there were galactic mergers and a lot of hydrogen was consumed in a phase of remarkable star formation.