12-Billion-Year-Old Galaxy Alaknanda Challenges Existing Models of Cosmic Evolution

Discovery of Ancient Galaxy ‘Alaknanda’ Redraws Early Universe Timelines

Indian astronomers have identified a remarkably mature ancient galaxy, named Alaknanda , whose existence challenges long-standing assumptions about how quickly galaxies evolved in the early universe. Observed through the James Webb Space Telescope (JWST) , the system exhibits a fully developed spiral structure despite having formed when the universe was barely 1.5 billion years old .

A Surprisingly Mature Spiral Structure

Alaknanda is estimated to be 12 billion years old and belongs to an epoch when galaxies were expected to be chaotic, clumpy and irregular. Instead, it shows a grand-design spiral pattern similar to the Milky Way. Two clearly defined spiral arms extend symmetrically from a central disc and bulge, accompanied by “beads-on-a-string” star clusters — classic indicators of an evolved spiral system.

India’s Significant Role in High-Redshift Astronomy

The discovery was led by researchers at the National Centre for Radio Astrophysics (NCRA) under the Tata Institute of Fundamental Research (TIFR) in Pune. Their analysis shows that Alaknanda spans around 30,000 light-years and contains nearly 10 billion stars , with a star-formation rate 20–30 times higher than that of the Milky Way.

Implications for Galaxy Formation Theory

Conventional models propose that galaxies require billions of years to stabilise into spirals. Alaknanda’s early maturity suggests that disc formation and mass accumulation occurred at far greater speeds than previously believed. Its mass — roughly ten billion solar masses — appears to have assembled within a few hundred million years, prompting reevaluation of early cosmic growth processes.

Exam Oriented Facts

• Age of galaxy: ~12 billion years

• Universe age at formation: ~10% of current age

• Location: ~12 billion light-years from Earth

• Star formation rate: 20–30× higher than the Milky Way