What controls the movement of galaxies?

In 1986, astronomers discovered the 'Great Attractor' 200 million light years away, powerful enough to control tens of thousands of galaxies. What is it and why is it so powerful? What impact will it have on our galaxy?

In the world we live in, countless objects are constantly moving and changing, and in the universe, these movements and changes are even more intense and on a larger scale. The theory of universal gravitation tells us that the strength of the gravitational force is usually related to the mass of the celestial bodies. 

Take the Earth-Moon system as an example, the mass of the Earth is larger than the Moon, so the Moon is attracted by the Earth's gravity and revolves around the Earth. In the Solar System, the mass of the Sun occupies most of the galaxy and becomes the gravitational center of the Solar System, the Earth and other celestial bodies revolve around the Sun. However, the Solar System is only a very small part of the universe. 

As humans continue to expand their exploration, we have discovered countless galaxies similar to the Solar System, which together form the Milky Way. There is also a supermassive black hole at the center of the Milky Way, which exerts an enormous gravitational pull and attracts countless galaxies similar to the Solar System to orbit around it. However, the Milky Way is not the end of the universe. On a larger scale, there are structures such as galaxy clusters and superclusters. 

Therefore, in academia, it is common to consider celestial bodies driven by the same gravity as a system to study. Recent research and observations have found that there is a gravitational anomaly located at the center of the Laniakea supercluster , which is predicted to be a huge gravitational source. This gravitational source is called the "Great Attractor".

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In the world we live in, countless objects are constantly moving.

When it comes to the discovery of the Big Attractor, we must refer to the history of human exploration of the universe. Human exploration of the early universe was mainly based on observation. When the Big Bang theory became the mainstream theory of the origin of the universe, thermal radiation, as a product left behind by the Big Bang, became part of the "cosmic microwave background" theory. 

According to this theory, microwave radiation is considered to be the oldest thing in the universe. By observing these microwave radiations, we hope to reveal the secrets of the origin of the universe. However, for a long time, scientists' research on the cosmic microwave background was limited to theoretical physics and they still did not know anything about measuring specific radiation. 

It was not until 1948, through many surveys and studies, that the temperature of our cosmic background radiation was determined to be 2.8 Kelvin. This discovery was an important step forward in human understanding of the universe. After the Big Bang, matter began to combine and change, forming various sources of heat. These sources of heat can guide us to explore the mysteries of the universe. 

Based on this fundamental theory, when scientists conducted a map of cosmic thermal radiation, they discovered that there was a small difference in temperature at the two ends of the Milky Way , this difference led people to speculate that our Milky Way was being attracted by some mysterious force. 

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Laniakea Supercluster.

It was not until the 1980s, when scientists were studying the redshift phenomenon of celestial objects, that they accidentally discovered that there were a large number of ancient galaxies located in the direction of Centauri and Hydra, which collided with each other and released enormous energy.  

The discovery has sparked speculation in the scientific community that there may be a huge gravitational force in this region. Surprisingly, this giant attraction lies on the same visual plane as the Milky Way's disk, allowing scientists to study it in more depth over the next few years, but due to the many layers of obstructions, they cannot peer into its mysteries. 

By observing the motion of surrounding galaxies, scientists discovered that this gravitational anomaly is about 150 million to 250 million light years away from Earth, and the energy it releases will affect surrounding galaxies within hundreds of millions of light years, causing them to be affected.

It wasn't until September 2014 that scientists made a breakthrough in the study of the giant gravitational force by defining the radial velocity of galaxies. They discovered the Laniakea Supercluster , a giant supercluster of galaxy clusters, with an estimated 100,000 Milky Way-sized galaxies in the entire cluster. Its diameter is about 520 million light-years, which means that this giant gravitational force affects the motion of celestial objects within a radius of 260 million light-years. 

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Such a huge source of energy has aroused great interest among scientists, who are eager to understand what it is and why it has such great power. These questions have become urgent topics of discussion in the astronomical community. Currently, the academic community has come up with several views on the nature of giant sources.

Most scholars believe that this force is definitely not caused by a black hole or some other celestial body. Based on previous observations, we know that there are often supermassive black holes at the centers of galaxies, such as Sagittarius A at the center of the Milky Way. The gravitational force it releases can affect the motion of the entire galaxy. 

However, this common phenomenon does not seem to explain the nature of the enormous gravitational forces. Astronomical observations show that to create the motion of a large number of super-galaxies with a collision range of 520 million light years, the mass of the giant attractor must be at least 20,000 times that of the Milky Way. That kind of mass is certainly not something a black hole can achieve. 

If black holes cannot explain the enormous gravitational pull, could it be the gravity generated by a galaxy itself? Observations show that there is a certain gap between the mass of the Magna Cluster of galaxies where the enormous gravitational pull is supposed to be and the mass where the enormous gravitational pull should be. So the gravity of the Magna Cluster is definitely not the source of the enormous gravitational pull. So which galaxy cluster could have so much energy?

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The diameter of this galaxy cluster can reach about 4 billion light years. (Illustration photo).

Judging by the motions of the surrounding galaxy clusters, the Sharpe Supercluster at a distance of 650 million light years could have such a strong gravitational pull. It is speculated that the diameter of this galaxy cluster could reach about 4 billion light years, and such a giant galaxy could be capable of generating enormous gravitational forces. 

Although it is uncertain whether they have 20,000 times the mass of the Milky Way, the Sharpe supercluster is widely considered to be the largest gravitationally bound object known and may exert enormous gravitational pull. 

However, it should be noted that our current understanding of the origin of the colossal gravitational force is very limited and this is only a hypothesis. Although the colossal gravitational force has such incredible power, it will not cause a catastrophic impact on the overall operation and stability of the universe. This is because the galaxies and structures in the universe were formed during the evolution of the universe and have a relatively balanced adaptation to the existence of the colossal gravitational force. When the colossal gravitational force acts, it also obeys the physical laws of the universe and the balance of forces. Although we cannot currently understand the nature of the colossal attractor, with the advancement of technology and the expansion of observational perspectives, one day we will unravel its mystery.