In a groundbreaking discovery that challenges established cosmic theories, two astronomers from Pune's National Centre for Radio Astrophysics (NCRA) have identified one of the earliest and most well-defined spiral galaxies ever observed in the universe. Using the powerful James Webb Space Telescope (JWST), researchers Rashi Jain and Yogesh Wadadekar spotted the galaxy, which they named 'Alaknanda' after the Himalayan river.
A Galaxy Born in Record Time
The newly discovered galaxy, Alaknanda, presents a cosmic puzzle. It is located a staggering 12 billion light-years away and spans approximately 30,000 light-years across. Analysis indicates it formed when the universe was merely about 1.5 billion years old. This timeline suggests the galaxy assembled its complex structure in record time, contradicting existing models which propose that galaxies in the early universe were chaotic and irregular, taking billions of years to develop stable forms.
"But Alaknanda has the textbook grand spiral design, two clear spiral arms wrapped around a bright centre," explained Rashi Jain. "It looks surprisingly similar to the Milky Way even though it came into existence when the Universe was only 10% of its present age."
Challenging Established Science
Co-author Yogesh Wadadekar emphasized the anomaly. "It looks like a regular, well-structured system. Such galaxies should take at least three billion years to develop stable spiral arms. Here, we are seeing a galaxy that seems to have completed this entire construction process in half that time." This finding directly challenges astrophysical models, as scientists believed the turbulent conditions shortly after the Big Bang prevented the rapid formation of such orderly, rotating disc galaxies.
The discovery, published on November 10 in the journal Astronomy and Astrophysics, was announced at a press conference at NCRA Pune. The scientists revealed that Alaknanda exhibits another remarkable property: an extremely rapid rate of star formation, nearly 30 times higher than the current rate in our Milky Way. Observations suggest the galaxy contains stellar mass equivalent to about 10 billion times the mass of the Sun.
Implications and Future Research
"Its spiral arms show a beads-on-a-string pattern that signals active star formation," Jain noted. This characteristic provides clues about its growth. Wadadekar suggested that the low light contribution from its central bulge indicates Alaknanda likely grew through smooth gas accretion rather than major galactic collisions. However, this process is theorized to take about a billion years to create spiral arms—longer than the 600-million-year window in which Alaknanda formed most of its stars.
"This mismatch points to gaps in our understanding of spiral galaxy formation," Wadadekar admitted. The team's next goal is to study the motion of stars and gas within Alaknanda using JWST's spectroscopic instruments. "If we can measure their velocities, we will be able to understand how this galaxy assembled so fast," he said. "We have one remarkable example today. Now we need to find more such galaxies to understand the bigger picture."
Rashi Jain, originally from Bharatpur in Rajasthan, is a PhD researcher who has been working with Wadadekar for one-and-a-half years. Wadadekar is an experienced astronomer who has studied galaxy evolution using various telescopes. Their work with JWST is revealing that the early universe was far more complex and mature than previously imagined, capable of producing elegant spiral structures like Alaknanda much sooner after the Big Bang than any theory predicted.
