Webb telescope unveils colossal ancient galaxy 'big wheel'
The James Webb Telescope has discovered a gigantic galaxy from the early universe, likely dating back 12 billion years. Scientists named it "Big Wheel," and their research was published in Nature Astronomy.
Profound observations from the James Webb Space Telescope have revealed a vast galaxy from the early universe. This cosmic giant, whose light has travelled over 12 billion years to reach us, was named the "Big Wheel" by researchers. Their discovery was documented in the scientific journal Nature Astronomy.
The discovery of a new spiral galaxy sheds new light on their formation
This gigantic disk galaxy existed within the first two billion years after the Big Bang, forming when the universe was just 15 per cent of its current age. This, in turn, challenges our understanding of how galaxies form.
What is a disk galaxy? It is a flat, rotating structure composed of stars, gas, and dust. Scientists describe disk galaxies as typically having distinct spiral arms extending outward from the dense central region. Our Milky Way galaxy is also a disk, characterised by beautiful spiral arms wrapping around its centre.
Studying disk galaxies such as the Milky Way and the newly discovered "Big Wheel" helps us understand how galaxies form, grow, and evolve over billions of years. This research is fundamental because understanding galaxies similar to ours can provide deeper insights into the cosmic history of our galactic home.
An unexpected discovery
Until now, researchers believed that galactic disks formed gradually over time, either through the smooth inflow of gas into galaxies from surrounding space or through mergers with smaller galaxies.
Rapid collisions between galaxies usually disrupt delicate spiral structures, transforming them into more chaotic shapes. However, "Big Wheel" quickly reached a surprisingly large size without losing its characteristic spiral shape, defying long-held theories about the growth of giant galaxies.
Detailed observations by the Webb Telescope show that the "Big Wheel" is comparable in size and rotation speed to the most prominent "super-spiral" galaxies in the contemporary universe. It is three times larger than comparable galaxies from that era and is one of the most massive galaxies observed in the early cosmos. Interestingly, despite its extreme size, the "Big Wheel" grows at a rate similar to that of other galaxies of the same cosmic age.
The discovery of a spiral galaxy is extremely rare
As described by researchers in the article, "Big Wheel" is located in an extraordinarily crowded region of space where galaxies are packed closely together, ten times denser than in typical areas of the universe. This dense environment likely provided the ideal conditions for the rapid growth of the galaxy. It probably experienced collisions gentle enough to preserve the galaxy's spiral disk shape. Additionally, the gas inflow into the galaxy must have been well-aligned with its rotation, allowing the disk to grow rapidly without disturbances. This is an ideal scenario.
The discovery of a galaxy like "Big Wheel" was improbable. According to current models of galaxy formation, we had less than a 2 per cent chance of finding this in our study," scientists said in an interview with Science Alert. They added that their discovery was shocking, likely because it was observed in an exceptionally dense region, unlike typical cosmic environments.
The fate of the newly discovered spiral galaxy remains a mystery
Beyond its mysterious formation, the Big Wheel's ultimate fate is another intriguing issue. Scientists predict that, given its dense environment, future collisions may significantly alter its structure, potentially transforming it into a galaxy comparable in mass to the largest observed in nearby clusters, such as Virgo.
"The discovery of 'Big Wheel' has unveiled another secret of the early universe, showing that our current models of galaxy evolution still require refinement," researchers said. With further observations and discoveries of massive, early galaxies like the "Big Wheel," astronomers can uncover more mysteries regarding how the universe built the structures we see today.
