Oldest Spiral Barred Galaxy Discovered, Challenging early Universe Theories
Astronomers have possibly identified the oldest spiral barred galaxy ever observed, dating back to just over 11.5 billion years after the Big Bang. The revelation, made using the James Webb Space Telescope, helps refine our understanding of when galactic bars – key structures in galaxy evolution - first emerged in the universe.
The galaxy, designated COSMOS-74706, was identified by Daniel Ivanov, a graduate student in physics and astronomy, utilizing data from the James Webb Space Telescope and the Space Telescope Science Institute (STScI). Confirmation came with additional data from the MOSFIRE instrument on the keck I telescope. The findings were presented January 8, 2026, at the 247th meeting of the American Astronomical society in Phoenix.
Galactic Engine
The central bar structure within COSMOS-74706 is notably significant. Bars act as a dynamic mechanism driving galactic evolution, channeling gas from the galaxy’s extremities towards its nucleus. This process fuels the central supermassive black hole and regulates star formation.
While previous reports have suggested the existence of potentially older objects,those claims relied on less conclusive evidence,such as gravitational lensing or redshift calculations,according to research.
Definitive Proof
Earlier analyses of potentially ancient galaxies were frequently enough inconclusive due to the limitations of relying on gravitational lensing or redshift measurements. These methods can introduce considerable margins of error or visual distortions, as reported by Live Science.
The validation of COSMOS-74706, however, was achieved through spectroscopy, a technique considered definitive for confirming the age and distance of cosmic objects.
“Finding such an organized structure just 2 billion years after the Big Bang helps us understand better the timescales on which galaxies reach maturity,” said Ivanov. ”It confirms that the young universe was capable of hosting complex systems much earlier than previously thought.”
The discovery fills a crucial gap between theoretical models and astronomical observation.COSMOS-74706 is classified according to the Hubble Sequence, a system that organizes galaxies based on their morphology. Unlike many primitive structures that appear as irregular disks, this galaxy already exhibits well-defined spiral arms emanating from a robust central bulge.
