Free Astronomy Magazine March-April 2024

37 MARCH-APRIL 2024 ASTRO PUBLISHING to generate powerful outflows.” The quasar the researchers ob- served, J2054-0005, has a very high redshift — it and the Earth are ap- parently moving away from each other very fast. “J2054-0005 is one of the brightest quasars in the dis- tant Universe, so we decided to tar- get this object as an excellent candidate to study powerful out- flows,” Hashimoto says. The re- searchers used ALMA to observe the outflow of molecular gas from the quasar. As the only telescope in the world that has the sensitivity and frequency coverage to detect molecular gas outflows in the early Universe, ALMA was key to this study. Speaking about the method used in the study, Salak comments: “The outflowing molecular (OH) gas was discovered in absorption. This means we did not observe mi- crowave radiation coming directly from the OH molecules; instead, we observed the radiation coming from the bright quasar — and absorption means that OH molecules happened to absorb a part of the radiation from the quasar. So, it was like re- vealing the presence of a gas by see- ing the ‘shadow’ it cast in front of the light source.” The findings from this study are the first strong evidence that powerful molecular gas outflows from quasar- host galaxies exist and impact gal- axy evolution at the early cosmic age. “Molecular gas is a very impor- tant constituent of galaxies because it is the fuel for star formation,” Salak concludes. “Our findings show that quasars are capable of sup- pressing star formation in their host galaxies by ejecting molecular gas into intergalactic space.” A rtist’s impression of an outflow of molecular gas from the quasar J2054-0005. [ESO/NAOJ/NRAO] !