I believe many friends know that there were nine planets in the solar system in the past, which we call the nine planets. But now our description of the solar system is all eight planets, which shows that one planet has been kicked out of the list of planets, and this planet is Pluto at the edge of the solar system.
Pluto can be said to be the first massive celestial body on the edge of the solar system observed by humans. As early as the 1840s, scientists predicted the position of Neptune. In the 20th century, scientists finally observed Pluto through astronomical telescopes. Once it was discovered, it was quickly defined as a planet by scientists. Since then, the solar system has nine planets.
However, with the rapid development of human science and technology, observation technology has been greatly improved, especially after the interstellar probes launched by humans in the last century came to the edge of the solar system, there are more observational photos and data of Pluto. Through these data, scientists have seen the different orbits of Pluto, and also found many celestial bodies around it.
At the same time, the probe also observed several celestial bodies of similar mass to Pluto, and some celestial bodies were even larger than it. If Pluto is also a planet, there are too many celestial bodies at the edge of the solar system. At this time, scientists began to rethink whether Pluto can be considered a planet? In the end, scientists decided to downgrade Pluto from the original planet to a dwarf planet, kicking it out of the list of planets.
The downgrade of Pluto is because scientists have redefined the standard of planets. The new standard definition of planets has three conditions. One is that it must revolve around the sun, and the second is that its shape must be spherical under the action of gravity. Thirdly, it can clear other small celestial bodies in its orbit except satellites.
Pluto meets the first two criteria, but it does not meet the third criteria. The reason is that there are a lot of small celestial bodies in Pluto’s orbit, and it has not eliminated these celestial bodies, so it is not a planet.
After Pluto was kicked out of the list of planets, the solar system became eight planets. For a long time, many people were still unable to adapt to this change. Many astronomers still use the nine planets to describe the solar system, and some people hope that the solar system will once again have the nine planets. Is this expectation possible?
It may be that people’s expectations have been responded to by the universe. When scientists calculated the orbits of some celestial bodies on the edge of the solar system, they found that their orbits were very abnormal and did not conform to the laws of celestial bodies. How is this going? You know, the laws of celestial bodies we apply are correct, and they are correct in the orbits of other celestial bodies, but why do they fail when they reach the edge of the solar system?
This result made scientists think of a possibility, that is, there may still be a massive planet at the edge of the solar system, the mass of this planet is several times that of the earth. Only the powerful mass and gravity of the planets can obviously affect the orbits of some celestial bodies on the edge of the solar system. When we calculated the orbits of these celestial bodies, we did not take this massive celestial body into consideration, so the orbital anomalies appeared.
This discovery made scientists excited, so there was a period of time for Planet Nine to search for heat, but because the edge of the solar system received very little light, and the planet itself does not emit light, even if Planet Nine exists, it is in our eyes. There is also a very dark celestial body. With the current observation technology of mankind, I am afraid it is difficult to find it.
Moreover, the orbit of Planet Nine may have reached tens of thousands of years. If there is no more accurate coordinate position, we will undoubtedly find it many times more difficult than finding a needle in a haystack. So how did this planet form? You know, according to the theory of planet formation, the solar system was born in a nebula 5 billion years ago.
99.86% of the matter in the nebula has become the sun, and very small matter has become the planet and other various asteroids. Whereas near the sun, the matter is denser, so more planets are formed, but at the edge of the solar system, the matter is sparse, and only relatively small celestial bodies can be formed, while celestial bodies as large as Pluto are already very large. It seems that it is difficult to form a super-Earth several times larger than the earth at the edge of the solar system.
Therefore, if there is such a huge planet at the edge of the solar system, it is likely to originate from other galaxies outside the solar system. It is possible that long ago, not long after the formation of the solar system, an exoplanet accidentally broke into the solar system, settled on the edge of the solar system, and became a member of the solar system.
If this planet is not a product of the solar system, it will be a huge piece of good news for scientists, and we can use it to understand the state of the extrasolar star system. Of course, we are still too early to be happy. Scientists can’t really determine whether Planet Nine exists. Although the anomaly of some celestial bodies at the edge of the solar system does tell us that there is a huge gravitational source there, but whether this gravitational source is a planet, At present, it is still unknown.
In addition to planets, there is also a kind of celestial body that can also cause a huge gravitational effect, and it is more concealed and difficult to be discovered by us. This kind of celestial body is the most mysterious and powerful black hole in the universe. I believe my friends all know about black holes. It is a kind of celestial body in the last century, Einstein’s theory of relativity conjecture. The existence of the black hole has now been confirmed, and scientists have also released the first photo of a black hole in mankind.
Black holes are also divided into different types according to their masses. The smallest black hole is the original black hole. Don’t look at it small, but its mass is equivalent to a super-Earth, and the two will produce huge gravitational effects. Some scientists speculate that the huge source of gravity at the edge of the solar system may be such a primordial black hole.
If Planet Nine is really a very small primordial black hole, it will be even more difficult for us to find it. To know the powerful phagocytic properties of black holes, even light can be swallowed, so we cannot directly observe the existence of black holes. However, because a massive black hole will form a bright accretion disk when it swallows a huge celestial body, we can be sure to find the black hole through the accretion disk.
But if it is some black holes with very small mass, they will basically not have accretion disks, so it is impossible to observe them with optical telescopes. Of course, scientists are not completely disappointed by this. Although black holes are more concealed, their powerful special abilities still have methods to observe.
Black holes have powerful radiation capabilities. If the gravitational source at the edge of the solar system is really a black hole, it will inevitably release some radiation unique to black holes. As long as we can detect some unusual radiation, there may be hope of finding it. Compared with a planet, scientists are more interested in black holes.
If Planet Nine is really a black hole, it will be of extraordinary significance to mankind, and we may be able to uncover part of the mystery of black holes through it. As the most mysterious and powerful celestial body in the universe, black holes may be related to some of the ultimate mysteries of the universe. Understanding it is equivalent to truly understanding the universe. We look forward to one day when scientists can truly understand whether there is a ninth planet at the edge of the solar system.