The universe is a vast and complex entity, with numerous mysteries that scientists are still trying to unravel. One such mystery concerns the metal factories in the early universe.
In a recent study, scientists used the James Webb Space Telescope to measure the metal content of the interstellar medium (ISM) in galaxies at the centre of the Milky Way. The study, conducted by a group at Cardiff University led by Stephen Eales, has shed new light on the formation of galaxies and the distribution of metals in the universe.
The researchers measured the mass of metals in 13 submillimetre galaxies (SMGs) at z ~ 4 in which the gas lies in a cold rotating disk. They used observations of carbon atoms, carbon monoxide molecules, and dust grains to estimate the metal masses. The values of the calibration factors for these tracers were obtained by the first attempt to calibrate all three tracers simultaneously. The researchers obtained very similar mass estimates from the different tracers, which were similar to the entire metal content of a present-day massive early-type galaxy.
The study revealed that the metal abundance increases with stellar mass, reaching a value of about twice the solar value at the highest masses. The metals in the outflows from these galaxies can explain quantitatively the long-standing conundrum that 75 per cent of the metals in present-day rich clusters are in the intra-cluster gas rather than in the galaxies.
The findings of the study are significant because they shed new light on the formation of galaxies and the distribution of metals in the universe. The researchers suggest a scenario for galaxy evolution in which massive galaxies reach a high metal abundance during their formation phase, which is then gradually reduced by dry mergers with lower mass galaxies.
The study also highlights the importance of the James Webb Space Telescope in advancing our understanding of the universe. The telescope is set to be launched in 2021 and will enable scientists to study the universe in unprecedented detail. It will allow them to observe the formation of galaxies and the evolution of the universe, as well as study the composition of planets and other celestial bodies.
The study also underscores the need for continued research into the origins of the universe and the evolution of galaxies. Scientists are still grappling with many questions about the universe, including how it began, how it evolved, and how it will end. The answers to these questions could have far-reaching implications for our understanding of the universe and our place in it.
The discovery by Eales et al. sheds new light on the metal content of galaxies and the formation of the universe. The findings of the study are significant because they provide new insights into the evolution of galaxies and the distribution of metals in the universe. The study also highlights the importance of the James Webb Space Telescope in advancing our understanding of the universe and the need for continued research into the origins of the universe and the evolution of galaxies. As scientists continue to unravel the mysteries of the universe, we can look forward to new discoveries that will challenge our understanding of the world around us.
Source: Eales, Stephen A., Haley L. Gomez, Loretta Dunne, Simon Dye and Matthew W.L. Smith. “Metal Factories in the Early Universe.” (2023). https://doi.org/10.48550/arXiv.2303.07376