Astronomers have identified the oldest stellar disk on Earth. milky waya discovery that reshapes our understanding of galaxy formation. This early disc was Pangu,it’s over 13 billion years old It represents the original structure from which the Milky Way grew. The discovery questions long-standing theories about when and how our galaxies came together and provides new insights into the early development of spiral galaxies.
A journey back to the beginning of the galaxy
researchers Chinese Academy of Sciences and University of Toronto We focused on tracing the oldest stars in the Milky Way to uncover their early structure. The research team used advanced techniques to study the movements of high-alpha stars, a class of stars rich in alpha elements that tend to form early in the history of galaxies. They have the number of stars 13 billion years old They formed a disk-like structure that they named it Pangunamed after the Chinese god of creation.
This stellar disk dates back to the time just after Earth. big bangabout 13.4 billion years agowhen the first stars began to form. Before this discovery, astronomers believed that the Milky Way had begun to form in a more structured manner around the Milky Way. 12.5 billion years agoHowever, the Pangu disk shows that the galaxy was already forming earlier than expected. The stars in this ancient disk had a total mass of about 3.7 billion solar massesan important part of the early Milky Way galaxy.
Growing steadily compared to other galaxies
One of the most surprising findings from this study was that Pango disc. While many similarly sized galaxies formed through violent mergers and chaotic events, the Milky Way’s early history appears to be more stable. Over time, the Pangu disk flattened into a shape typical of spiral galaxies, but its initial shape was about the same height and width, indicating that the formation process was not very intense.
By the time the Milky Way reaches peak star formation 11 billion years agowere producing stars at a rate of about . 11 solar masses per year. This relatively smooth development sets the Milky Way apart from other spiral galaxies, which often experience multiple disruptions during their formation. PanGu disk only occupies the current. 0.2% Of the Milky Way’s current mass, most of its material was acquired through mergers with smaller galaxies over billions of years.
Challenging traditional models of galaxy formation
The discovery of the Pangu disk not only sheds light on the history of the Milky Way galaxy, but also casts doubt on traditional models of galaxy formation. Astronomers previously believed that large galaxies like the Milky Way evolved through a series of chaotic mergers, resulting in irregular growth and frequent reorganization. However, its existence is Pango disc This suggests that the Milky Way galaxy followed a more orderly and continuous growth path.
This discovery further complicates our understanding of how galaxies form and evolve. Simulations of galaxy formation suggest that most galaxies are: milky way Although humanity experienced significant turmoil early in its history, the Pangu disk shows that such turmoil was not as severe for our galaxy.
Future research
The discovery of the Milky Way’s ancient stellar disk opens new avenues for research into the early development of galaxies. As astronomers continue to study stars within Earth, Pango discThey want to learn more about the conditions that have allowed the Milky Way to grow so steadily compared to other galaxies. These discoveries will also help scientists refine models of galaxy evolution, giving them a clearer picture of the processes that took place after the universe formed. big bang.
Research suggests that the peak of star formation in the Milky Way Galaxy is 11 billion years agoAnd understanding how this disk evolved during and after that period could provide important insights into the development of other spiral galaxies.
