1. The mysterious structure at the center of the Milky Way
Milky Wayis a large and complex system of celestial bodies in the universe, composed of hundreds of billions of stars and a large amount of interstellar matter. However, these substances are not evenly distributedMilky Wayand presents a peculiar structure. Back in the early 20th century,ScienceThe family is starting to get rightMilky WayObservations and studies were conducted, but they did not realize it until the 50s of the 20th centuryMilky WayThere is a spiral arm structure inside. Betty Miller and William Morgan were among the first to come up with itMilky WayThere is a spiral arm structureAstronomyScientists, who, through observation and data analysis, found in:Milky WayThere is a bright and dense band-like structure in a specific area, which is the spiral arm. With the advancement of technology, modernAstronomyScientists are able to observe more accuratelyMilky WayThe structure of the spiral arm, revealing its mysterious nature.
Milky WayIt is the home of the universe that we live in, and in its vast system, there are many star clusters, nebulae, stars and other celestial bodies. But in this interstellar world, the distribution of various substances is not uniform, but a peculiar structure is formed - spiral arms. They are called "spiral arms" because they wrap aroundThe center of the Milky WayThe orbit of the star is in a spiral shape. These spiral arms are inThe center of the Milky WayThe result is a unique and complex scene.
2. Classification and research of spiral arms
Initially, Miller and Morgan wouldMilky WayThe spiral arm structure is divided into four main branches, which are:PerseusSpiral arm,OrionSpiral arm, pedestal-Sagittarius spiral arm and rectangular ruler spiral arm. Among them,OrionThe spiral arm is the most familiar because our solar system is located in it. Initially, of courseMilky WayThe perception of the spiral arm is not accurate with the radioAstronomyLearn andInfraredThe development of observation technology, modernAstronomyScientists are able to draw more accuratelyMilky WayThe spiral arm structure.
In the pairMilky WayIn the in-depth study,ScienceThe spiral arms were classified and studied in detail according to the distribution and properties of the stars. In addition to the original four swivel arms, more swivel arms have been found today, such as the Cancer swivel arm, the secretary seat swivel arm, etc. There are also transition zones in the area between these booms, which we can think of as bridges connecting the different booms. By studying the characteristics and formation mechanisms of these spiral arms,ScienceThe family was better understoodMilky Wayevolutionary history and tectonic characteristics.
3. The reason for the formation of the spiral arm structure
WhyMilky WayWill there be a spiral arm structure?ScienceScholars have proposed an explanation that the spiral arm structure is triggered by density waves of interstellar matter. In densely populated regions, the gravitational pull is relatively strong, causing the stars to move relatively slowly within the spiral arms, causing them to gradually clump together, further increasing the density of matter in that region. This "density wave" effect leads to the formation of the spiral arm and keeps it in a relatively stable structure.
Milky WayThe formation of spiral arms is a complex and dynamic process involving the interaction of interstellar matter and the influence of gravitational fields. Within the spiral arms, the stars interact with each other, pulling and excites each other through gravitational pull, creating a density wave effect. This density wave effect led to the acceleration and aggregation of interstellar matter, culminating in the formation of spiral arm structures. This process involves the interaction of multiple factors, such as gravity, stellar motion, and the interstellar medium. Together, these factors drive the formation of the spiral arm, making it a relatively stable structure.
4. The fracture phenomenon of the spiral arm structure
Although the spiral arm structure seems to be stable, butScienceThe family has discovered something unusual. Through Spitzer infrared spaceTelescopesAstrophysicists at the California Institute of Technology found that there are some stars on the Sagittarius spiral arm that leave the spiral arm at a prominent angle, and from a macroscopic perspective, it looks like the spiral arm has broken. However, this fracture is actually a visual misconception and is caused by the influence of the interstellar medium, and does not mean that the spiral arm will actually break.
The fracture phenomenon of the spiral arm is oneAstronomyLearnedOptical illusions, similar to the bending effect of light rays as they pass through a refractive medium. On the Sagittarius spiral arm, there is some material known as the interstellar medium, which interacts with the stars in the spiral arm, causing some of the stars to be observed at a prominent angle away from the spiral arm. This phenomenon does not mean that the spiral arm is really broken, but is affected by the dynamic changes in the interstellar medium. Therefore,Milky WayThe structure remains intact, and the spiral arm structure is still stable.
Milky Wayis a large and complexStructure of the universe, in which the spiral arm is one of its unique forms. ScienceThrough observation and research, the formation mechanism and characteristics of the spiral arm structure have been revealed. The spiral arm structure is caused by density waves of interstellar matter, and the stars move within the spiral arm to gradually gather together to form a bright and dense ribbon-like structure. Despite the seemingly stable spiral arm, butScienceThey also found some unusual phenomena in the spiral arm structure, such as the visual effect of the fracture of the Sagittarius spiral arm. However, this fracture is only a visual effect and is actually caused by the influence of the interstellar medium, and does not mean that the spiral arm will actually break. WholeMilky WayThe structure relies on gravity andDark matterThe role remains stable and anyStructure of the universeIt's hard to break easily. Dark matterThe presence of galaxies plays an important role in maintaining the stability and shape of galaxies. Although at the moment forDark matteris still limited, and there is no direct observational evidence, but this hypothesis helps explain the structure and evolutionary history of the universe.