Shulou(Shulou.com)11/24 Report--

Last time, it was completely unrealistic to see the whole picture of the Milky way by sending detectors out of the Milky way. now our understanding of the shape of the Milky way rod spin mainly comes from indirect observations. for example, the observation of the hydrogen 21-centimeter line in interstellar space through radio telescopes.

To study the Milky way, in addition to studying the Milky way itself, we can also indirectly infer the situation of the local galaxy by observing similar galaxies around us. After all, based on cosmological principles, the universe is uniform and isotropic. No matter it is a star or a galaxy, any celestial body is not unique as long as it is placed in the universe.

Especially when studying goals with a large time span, such as the evolution of the sun, we can't wait for it to change all the time. We can only build a unified model by studying other similar stars at different stages of evolution, and then replace the sun into this model to speculate about its past life and afterlife.

It is the same to study the evolution of the Milky way Milky way, we first sift out some galaxies from the vast universe, build the evolution model of galaxies based on them, and then replace the Milky way, so as to speculate its evolution process.

But whether it is stars or galaxies, these man-made models are bound to be rough, and they are only temporary models based on the limited data available. As more and more accurate observation data are obtained, the model will be updated and become more and more perfect.

This is also a scientific research method that is often mentioned. Science does not represent the right, let alone the truth, it is more like a methodology that guides us closer to the truth step by step.

Back to studying the Milky way through similar galaxies. In fact, there is a galaxy in the local group near the Milky way that is very similar to our Milky way, yes, the famous Andromeda galaxy (M31).

The Andromeda galaxy is like a "magnified version" of the Milky way, both in its overall outline and in its internal spiral structure. Even in recent years, scientists have found that it seems to have a rod-shaped core, suggesting that it is likely to be a rod spiral galaxy like the Milky way.

Even the halos on the periphery of the Andromeda galaxy are similar to those of the Milky way, where stars are usually metal-poor "older" stars. This suggests that the Andromeda galaxy, like the Milky way, has undergone a similar evolution, including its gradual growth to its present size through the massive annexation of surrounding dwarf galaxies over a period of 10 billion years.

In addition to mature galaxies such as Andromeda, astronomers seem to have seen the Milky way in their infancy in previous images taken by the Webb telescope.

As we have introduced before, this is a deep-field picture of thousands of galaxies in the sand-grained sky. Under the action of the gravitational lens of the foreground galaxy cluster, some background objects are magnified 10 to 100 times. In the elongated and magnified background image, astronomers see a slender structure surrounded by bright spots.

This is a distant galaxy with a redshift of 1.378, and we see it still about 4 billion years after the Big Bang. The small bright spots around it are actually ancient globular clusters, each made up of millions of stars. These star clusters surround the galaxy like dazzling fireworks, so people gave the galaxy a vivid name-Spark.

Through the analysis of metal elements and evolutionary models, astronomers believe that spark galaxies are very similar to the Milky way, much like the infancy of the Milky way. At that time, the "Milky way" (that is, the spark galaxy) was only 3% of the mass of today's Milky way, when it was busy gobbling up surrounding satellite galaxies and globular clusters. It is expected that in another 90 or tens of billions of years, it will reach the quality of the Milky way today.

Such a "juvenile mirror" of the Milky way is a treasure for astronomers, and it is very helpful to study the evolution of our Milky way. Because we can't know directly about the early events of the Milky way galaxy today. But with this sample, the "childhood" appearance of the Milky way, which originally existed only in theory, including behavior will become traceable.

For example, the puzzle that has long plagued astronomers is how globular clusters came about. For the globular clusters in the Milky way, we only know that they are very old, but we still don't know exactly how old they are and how they were formed at that time.

Now with spark, a young mirror galaxy, we can more easily determine the age and condition of its globular clusters. After all, it's not easy to tell 78 from 88, but it's easy to tell between 8 and 18.

It is now believed that globular clusters and early galaxies were born in primitive gas clouds in the universe (such as high-density neutral hydrogen clouds). Because the composition of galaxies is more complex and clusters are relatively simple, this is why the stars in some globular clusters are older than their galaxies.

However, in order to better understand the evolution of spark galaxies and their surrounding clusters, astronomers need to observe more similar galaxies and clusters in order to further improve the relevant theory.

This article comes from the official account of Wechat: Linvo says ID:linvo001, author: Linvo

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.