b'8 Carnegie Science|Spring/Summer 2020Ancient Gas Cloud ShowsFirst Stars Formed QuicklyTheir findings reveal that the first generation of stars formed more quickly than previously thought.T he discovery of a 13 billion-year-old cosmic cloud ofthis material spread out, it cooled,Lead author of the study, Eduardo gas enabled a team of Carnegie astronomers toand the particles coalesced into perform the earliest-ever measurement of how theneutral hydrogen gas. The universe was enriched with a diversity of chemicaluniverse stayed dark until gravityBaados, was the Carnegie-Princeton elements. Their findings reveal that the firstcondensed matter into the firstFellow at the Observatories and Princeton University from 2015 to generation of stars formed more quickly than previouslystars and galaxies.2018. In January of 2019, he joined thought. The research, led by former Carnegie-Princeton fellowAll stars act as chemicalthe scientific staff at the Max Planck Institute for Astronomy.Eduardo Baados and including Carnegies Michael Rauch andfactories, synthesizing almost allImage courtesy Cindy Hunt, Carnegie Tom Cooper, was published by The Astrophysical Journal of the elements. When the originalInstitution for Science. The Big Bang started the universe as a hot, murky soup ofstars exploded as supernovae, they extremely energetic particles that was rapidly expanding. Asspewed out the elements that they created, seeding the surrounding gas. Subsequent generations of stars incorporated these elements and steadily increased the chemical abundances of their surroundings. But the first stars formed in a pristine, cold universe. Consequently, these initial stars produced elements in different proportions than those synthesized later, which were formed in SUPPORT: The team used the Magellan telescopes at A European Research Council grant Cosmic Dawn, a U.S. National Science FoundationCarnegies Las Campanas Observatory in Graduate Research Fellowship, and directChiles Atacama Desert for their discovery. funding from the MIT Undergraduate ResearchImage courtesy Matias del Campo, Opportunity program supported this work. Carnegie Institution for Science'