New insights into the mystery of our universe’s beginnings
By Simra Ahmad
Photo Credit: James Webb Space Telescope Illustration by NASA
The astronomers at the Danish Cosmic Dawn Center at the Niels Bohr Institute and STU Space in Copenhagen discovered a still-forming galaxy which emitted its light 13 billion years ago. Kasper Elm Heintz’ leader of the study and assistant professor at the Cosmic Dawn Center, credits the James Webb Space Telescope (JWST) as the reason for the discovery.
Between mature galaxies, there was a large amount of unpolluted gas flowing towards galaxies as gravity collected gas that had started forming stars; however, it was at a pace that the stars couldn’t keep up with. When this occurs, the formation of a galaxy begins. According to Patrick Kelly, the senior author of the article on this discovery and an assistant professor at the University of Minnesota,
“The galaxy’s volume is roughly a millionth of the Milky Way’s, but we can see that it’s still forming the same numbers of stars each year”.
Clusters of galaxies led to gravitational lensing, a process where the mass in a galaxy bends and magnifies the light, making this background galaxy shine twenty times brighter than it otherwise would have, allowing researchers to study this tiny miracle. As the James Webb Space Telescope collects ten times the light than the Hubble Space Telescope and is more sensitive to longer wavelengths in the infrared spectrum, it captured this beauty brilliantly. Therefore, scientists were able to measure, through mass spectroscopy, how far away the galaxy was.
“It’s basically getting a snapshot of our universe in the first five hundred million years of its life”. Ismael Pérez-Fournon, a researcher at the University of La Laguna who participated in the study, exclaims. This discovery is the first time the ongoing process of galaxy formation can be studied. As it’s the first galaxy to be discovered at this distance, it could further expand our understanding of how our very own galaxy was formed. Without NASA, the National Science Foundation and the Spanish State Research Agency support and funding, the research which led to this discovery would have been monumentally difficult to achieve.
Experts have also highlighted that observing galaxies at such an early stage might answer questions relating to the universe's re-ionisation. After the Big Bang, recombination, the first significant gas transition during which charged electrons and protons form neutral hydrogen atoms, occurred. Re-ionisation, the second major phase of gas transition, is the phenomenon that took place where electrically neutral hydrogen atoms were re-ionised and split again; it's also the reason the Cosmic Dark Ages came to an end. However, the Big Bang is still a mystery, even the intricacies of the known stages.
Brant E. Robertson, an Astronomy and Astrophysics Professor from the University of California, supported this theory of the JWST discovery being vital for scientists to research the re-ionisation period further. He also explains that high-redshift galaxies usually relate to finding the earliest forming systems, which help explore the nascent Universe. This could rewrite our understanding of cosmic re-ionisation and the beginning of galaxy formation. Robertson even included that JWST could be used for future missions and revolutionise our understanding of the universe.
With more and more of these discoveries, we are getting closer to solidifying the Big Bang and finding concrete evidence of the universe’s beginning.
