Galactic Mysteries: The Enigma of a Non-Rotating Ancient Galaxy

New discoveries in astronomy are opening doors to a more complex understanding of galaxy evolution in the early universe. In a recent study, scientists unveiled a massive galaxy from the universe’s first era that shows no signs of rotation, a finding that surprises researchers and challenges current theories about how galaxies form and evolve.

Rotation: The Assumed Foundation of Galaxy Formation

According to prevailing astronomical models, galaxies are believed to start rotating from the moment they form. The inflow of gas towards the center and the gravitational pull of matter create the angular momentum that drives this circular motion. Over time, interactions between galaxies, such as collisions and mergers, can influence this rotation, either enhancing or diminishing it.

However, the real surprise came from galaxy XMM-VID1-2075, observed when the universe was less than two billion years old. This galaxy showed no rotation, indicating that changes in motion can occur more rapidly than previously thought.

A Giant Galaxy with an Early Formation History

The galaxy XMM-VID1-2075 is considered one of the largest galaxies discovered in the early universe, according to the research team from the University of California, Davis. Previous studies using the W.M. Keck Observatory revealed that this galaxy already contains more stars than the Milky Way and has ceased forming new stars, making it an intriguing target for future studies.

Webb Telescope: A New Window into the Early Universe

The James Webb Space Telescope has revolutionized the ability to study distant galaxies. Using this telescope, scientists tracked the movement of material within galaxy XMM-VID1-2075 and two other galaxies from the same era. They discovered that one of these galaxies rotates, another exhibits an irregular structure, and the third, our focus, shows no rotation but rather strong random motion of its stars.

What Could Halt a Galaxy’s Rotation?

Researchers are striving to understand why this galaxy stopped rotating so quickly. One hypothesis is that a significant collision might be responsible for this halt. If two galaxies rotating in opposite directions collide, their motions could cancel each other out, leading to a stop in rotation.

Observations indicate an excess of light on one side of the galaxy, suggesting the presence of another body interacting with the system, possibly altering its dynamics.

Conclusion

Research teams continue to explore more non-rotating galaxies in the early universe by comparing observations with computer simulations. Understanding how common these galaxies are will help test current theories about galaxy formation. Thanks to advanced observational techniques, scientists can now revisit how galaxies emerged and evolved over time.