A groundbreaking study carried out by an international research team, which includes scientists affiliated with The University of Manchester and the University of Victoria, has unveiled that disk-shaped galaxies resembling our own Milky Way were more prevalent and emerged earlier in the universe than previously believed.
Employing the James Webb Space Telescope, a team of researchers hailing from institutions such as The University of Manchester in the UK and the University of Victoria in Canada has made a fascinating discovery: galaxies akin to our Milky Way dominate the cosmos and are surprisingly widespread.
The University of Manchester, while announcing this new research, revealed that disk galaxies were ten times more abundant in the universe’s early stages than previously estimated. This groundbreaking study was published in The Astrophysical Journal on September 22 and underwent rigorous peer review.
For a considerable period, astronomers held the notion that newly formed galaxies that began merging shortly after the Big Bang approximately 13.7 billion years ago lacked noticeable structures such as spiral arms, bars, or rings. These distinctive galactic features were believed to have taken shape at least six billion years post-Big Bang. However, the latest study challenges this conventional wisdom by suggesting that these intricate structures might have appeared as early as 3.7 billion years after the Big Bang, nearly at the universe’s inception.
Christopher Conselice, an astronomy professor at The University of Manchester and a co-author of the study, remarked, “In light of our findings, astronomers need to reconsider our understanding of the formation of the first galaxies and the evolutionary processes that have unfolded over the past 10 billion years.”
The existing theory asserted that disk galaxies remained scarce until the universe had reached a “middle-aged” phase.
Lead author Leonardo Ferreira from the University of Victoria commented, “For more than three decades, it was widely believed that these disk galaxies were uncommon in the early universe, primarily due to the frequent violent interactions between galaxies. The fact that the Webb telescope has uncovered so many of them underscores the remarkable capabilities of this instrument and hints at the early formation of galaxy structures—much earlier than previously envisioned.”
According to the study’s findings, the research team categorized a sample set of nearly 4,000 galaxies from the early universe based on their shapes, including disks, point sources, and spheroids. They further divided them into smooth or structured categories, with structured galaxies displaying bursts of star formation and indications of mergers with other galaxies. These groundbreaking findings underscore the necessity for fresh concepts that can elucidate the evolution of galaxies over the past 10 billion years.