Is the Sun really common in the Milky Way?

99.8% of the mass in the Solar System is occupied by the Sun, as the only star, the Sun firmly holds a dominant position in the entire stellar system.

In the Milky Way, single star systems like our Sun are uncommon.

According to statistics, 85% of the stars in the Milky Way belong to multiple star systems such as double stars and triple stars . If the stars have larger masses, this ratio will increase even more. However, recently astronomers have discovered that this rule does not seem to apply near the center of the Milky Way.

Devin Chu of the University of California, Los Angeles (UCLA) led his team in analyzing stars near the black hole at the center of the Milky Way. They used the Keck Observatory in Hawaii to spend 10 years tracking 28 stars orbiting the supermassive black hole.

In astronomy, an optical binary is when two stars appear close together when viewed from Earth. There are two types of optical binaries: visual binaries, which are true binary star systems, and apparent binaries, which are two stars that appear close together, but are actually very far apart.

The black hole at the center of the Milky Way, also known as Sagittarius A*, is about 44 million kilometers in diameter and has a mass 4.3 million times that of the Sun, making it a typical supermassive black hole. The environment near the black hole is complex and chaotic, and its gravity will strongly impede celestial bodies and even swallow stars. Therefore, scientists generally believe that it is difficult for new stars to appear near black holes.

However, among the stars the researchers monitored, 16 were relatively young, born just over 6 million years ago, and they were all very large, with masses typically 10 times the mass of the Sun.

This raises many questions. The reason is that it is very difficult to form new stars near a black hole, and these young stars do not have enough time to migrate here after forming elsewhere. On the other hand, scientists have analyzed the spectra of these stars and found that they are all single stars.

The highest probability of stars forming a binary system near the Sagittarius A* black hole is 47%.

As we mentioned above, multiple star systems are a normal and common state of the Milky Way, especially for high mass stars, the probability of forming binary or even triple star systems is relatively high.

The researchers put together the observations and concluded that the highest probability of stars forming a binary system near the black hole at the center of the Milky Way is about 47%. All appear to be related to the supermassive black hole Sagittarius A*.

The researchers put forward two possibilities, the first is that the black hole's gravity broke up the original binary system, and the remaining star was thrown away by the black hole's gravity. This is entirely possible in both theoretical and practical situations. Scientists have discovered many stars "running away" from the Milky Way at high speeds, and they often fly towards the outside of the Milky Way at speeds of more than 1.6 million km/h.

The gravitational pull of a black hole is strong enough to break apart binary star systems.

Another possibility is that the stars are actually much older than they appear. The gravitational pull of a black hole is strong enough to tear binary star systems apart, causing them to collide and merge. This could also explain why such young stars appear in such an extreme environment.

In a way, these stars can be considered lucky stars. Because running around a black hole is extremely dangerous, because in such a situation, many celestial bodies are likely to be torn apart and swallowed. For objects near a black hole, the most terrifying thing is the tidal force of the black hole .

The gravitational force on the side of the star closest to the black hole is much stronger than on the other side.

We all know that the gravitational force of two objects is related to the distance between them. The gravitational force on the side of the star closest to the black hole is much stronger than the other side, when the difference in gravitational force between the two sides is greater than the gravitational force of the star itself, the star will stretch in its own direction of motion like a noodle.

From a sphere to an ellipse, and finally a long bar. The next thing the star faces is the fate of disintegration, and the torn apart star will rapidly approach the black hole until it is swallowed up.

A black hole with a mass of 100 billion solar masses would evaporate in 2×10^100 years.

Although a black hole may seem so terrifying that nothing can stand against it, it will eventually die.

While the black hole is swallowing matter, it is also radiating matter outward. In other words, it will not only expand indefinitely but also consume itself. Scientists have calculated that a black hole with a mass equal to 100 billion solar masses will evaporate within 2×10^100 years, and during the evolution of a black hole, if there is not enough matter to suck in, the black hole will accelerate the decay process.

However, considering the existence of human civilization, it is difficult for us to see the end of black holes. But the study of black holes has become a necessary need for mankind, because behind it there are too many mysteries that we do not know.