Astronomers have discovered a beautiful, well-formed spiral galaxy from a time when the universe was still very young—only 1.5 billion years after the Big Bang.
Using NASA’s James Webb Space Telescope (JWST), researchers Rashi Jain and Yogesh Wadadekar found a galaxy that looks remarkably similar to our own Milky Way, even though such organized structures were not expected to exist so early.
They named the galaxy Alaknanda, after a Himalayan river that pairs with the Mandakini, echoing the meaning of “Milky Way” in Hindi.
This discovery, made at the National Center for Radio Astrophysics in Pune, India, and published in Astronomy & Astrophysics, challenges long-held ideas about how quickly galaxies can form and mature.
Traditionally, scientists believed that early galaxies should appear messy and irregular, because they had not yet had time to gather enough gas, settle into rotating disks, or develop the spiral arms we see in mature galaxies today.
Yet Alaknanda defies those expectations.
It already shows two clear, sweeping spiral arms wrapped around a bright central bulge and stretches about 30,000 light-years across.
Even more surprising, it is forming new stars at a rate 20 times faster than the Milky Way today. About half of its stars seem to have formed in just 200 million years—an incredibly short time on cosmic scales.
According to lead author Rashi Jain, Alaknanda displays a level of structural maturity normally seen in galaxies billions of years older.
Its existence suggests that the processes that build spiral galaxies—gas inflow, disk settling, and possibly the formation of density waves—can happen far more quickly than current models predict.
One reason we can see Alaknanda so clearly is that it lies behind a massive galaxy cluster called Abell 2744, or Pandora’s Cluster.
The cluster’s strong gravity acts like a cosmic magnifying glass, bending and amplifying the galaxy’s light. Thanks to this gravitational lensing, JWST was able to capture the galaxy’s spiral structure in remarkable detail.
Jain and Wadadekar analyzed JWST images of Alaknanda taken through 21 different filters, allowing them to measure its distance, star-forming activity, and overall makeup with great accuracy. Their findings add to a growing body of evidence that the early universe was much more advanced and dynamic than expected. Other disk-shaped galaxies have been discovered at similar distances, but Alaknanda stands out as one of the clearest examples of a classic “grand-design” spiral from this era.
Scientists are now exploring how such a galaxy could have formed so quickly. Future observations with JWST and with ALMA in Chile may reveal whether the galaxy’s disk is rotating smoothly or is more turbulent, offering clues to its history.
The discovery of Alaknanda reshapes our understanding of how fast galaxies can grow and evolve. It suggests that the conditions that eventually led to planets—and life—may have appeared much earlier in the universe than once believed.
Source: KSR.
