A new discovery from the James Webb Space Telescope (JWST) has revealed a spiral galaxy named Alaknanda, formed just 1.5 billion years after the Big Bang. This finding challenges existing theories about galaxy formation, suggesting that well-structured galaxies could emerge much earlier than previously believed. Researchers Rashi Jain and Yogesh Wadadekar from the Tata Institute of Fundamental Research in Pune, India, identified this remarkable galaxy, which bears a resemblance to our own Milky Way.
The discovery was published in the journal Astronomy & Astrophysics on December 2, 2025. Alaknanda stands out as a grand-design spiral galaxy, characterized by its two symmetric arms and a bulging center, spanning approximately 30,000 light-years. Its formation during a time when the universe was roughly a tenth of its current age poses significant implications for our understanding of cosmic evolution.
A Surprising Discovery in the Early Universe
Traditionally, astronomers believed that classic spiral galaxies like Alaknanda required billions of years to develop. The prevailing view suggested that early galaxies should appear irregular and chaotic, still in the process of assembly. However, Alaknanda defies these expectations, showcasing a well-organized structure with two sweeping arms and an impressive star formation rate.
Currently, Alaknanda is producing new stars at a rate approximately 20 times that of the present-day Milky Way, with nearly half of its stars forming within just 200 million years. Jain explains, “Alaknanda has the structural maturity we associate with galaxies that are billions of years older. Finding such a well-organized spiral disk at this epoch tells us that the physical processes driving galaxy formation can operate far more efficiently than current models predict.”
The Role of Gravitational Lensing
The galaxy’s discovery was facilitated by its location near a massive galaxy cluster known as Abell 2744, or Pandora’s Cluster. The immense gravity of this cluster bends and magnifies light from distant objects, an effect known as gravitational lensing, which made Alaknanda appear significantly brighter and allowed JWST to capture its intricate spiral structure in fine detail.
Jain and Wadadekar analyzed images of Alaknanda taken through 21 different filters, each providing insights into its light composition. This extensive data set, part of JWST’s UNCOVER and MegaScience surveys, enabled researchers to estimate the galaxy’s distance, dust content, stellar population, and star formation rate with remarkable accuracy.
The implications of Alaknanda’s existence extend beyond its aesthetic beauty. The discovery prompts a reevaluation of the cosmic timeline and suggests that the early universe was capable of forming complex and stable structures much more rapidly than previously thought.
As Jain notes, “Finding such a well-organized spiral disk at this epoch forces us to rethink our theoretical framework.”
The findings also ignite discussions on how Alaknanda’s spiral arms developed. Possible explanations include the steady accumulation of cold gas or gravitational interactions with smaller companion galaxies. Future observations, potentially utilizing JWST’s spectroscopic instruments or the Atacama Large Millimeter Array (ALMA) in Chile, may shed light on these processes by measuring the galaxy’s rotation and overall dynamics.
This remarkable discovery not only highlights the advanced capabilities of the JWST but also underscores the need for ongoing exploration of the universe’s early history. As astronomers continue to study Alaknanda and similar galaxies, they may uncover more evidence that reshapes our understanding of how galaxies, including our own, came to be.
