I believe many of you know that in the past, there were nine planets in the solar system, which we call the nine planets. But now our descriptions of the solar system are all eight planets, which means that one planet has been kicked out of the list of planets, and this planet is Pluto on the edge of the solar system.
Pluto can be said to be the first massive object on the edge of the solar system observed by human beings. As early as the 1840s, some scientists predicted the position of Neptune. In the 20th century, scientists finally observed Pluto through astronomical telescopes. Once it was discovered, it was soon defined as a planet by scientists. From then on, there were nine planets in the solar system.
However, with the rapid development of human science and technology, the observation technology has been greatly improved, especially after the interstellar probe launched by human beings in the last century came to the edge of the solar system, there are more observation photos and data on Pluto. Through these data, scientists can see Pluto’s different orbit, and find many celestial bodies around it.
At the same time, the probe also observed several objects with the same mass as Pluto, and some objects are even larger than Pluto. If Pluto is also a planet, there are too many celestial bodies on the edge of the solar system. At this time, scientists began to rethink whether Pluto is a planet? In the end, scientists decided to downgrade Pluto from the original planet to a dwarf planet and kick out the planet list.
Pluto’s demotion is due to scientists’ redefinition of the standard definition of planets. The new standard definition of planets has three conditions: one is that it must revolve around the sun; the second is that it must be spherical in shape under the action of gravity; and the third is that it can clear other small bodies in its orbit except satellites.
Pluto meets the first two criteria, but it does not meet the third. The reason is that Pluto has a lot of small objects in its orbit, and it doesn’t remove them, so it’s not a planet.
After Pluto was kicked out of the planet list, the solar system became eight planets. For a long time, many people could not adapt to this change. Many astronomy enthusiasts still use nine planets to describe the solar system, and some people expect the solar system to have nine planets again one day. Is it possible to realize this expectation?
It may be that people’s expectations have been responded by the universe. When scientists calculate the orbits of some celestial bodies on the edge of the solar system, they find that their orbits are very abnormal and do not conform to the laws of celestial bodies. What’s going on? We should know that the laws of celestial bodies are correct. They are correct in the orbits of other celestial bodies. But why do they fail at the edge of the solar system?
This result makes scientists think of a possibility that there may be a massive planet on the edge of the solar system, which is several times more massive than the earth. Only the strong mass and gravity of planets can significantly affect the orbits of some celestial bodies on the edge of the solar system. When we calculate the orbits of these celestial bodies, we don’t take this massive celestial body into account, so the orbital anomalies will appear.
This discovery excited scientists, so we had the ninth planet for a period of time to look for heat. However, because the solar system edge receives very little light, and the planet itself does not emit light, so even if the ninth planet exists, it is a very dark object in our eyes. I’m afraid it’s hard to find it with the current observation technology of human beings.
Moreover, the orbit of the ninth planet may have reached tens of thousands of years. If we don’t have a more accurate coordinate position, it is much more difficult to find it than looking for 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 cloud five billion years ago.
99.86% of the matter in the nebula makes the sun, and the smallest amount makes planets and other asteroids. In the places close to the sun, the matter is dense, so there are many planets formed. However, in the edge of the solar system, the matter is relatively scarce, and only some relatively small objects can be formed. The objects as big as Pluto are already very large, and it seems that it is very 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 on the edge of the solar system, it is likely to come from other galaxies outside the solar system. It is possible that a long time ago, not long after the formation of the solar system, an exoplanet accidentally intruded 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 great good news for scientists, through which we can understand the situation of extrasolar star system. Of course, it’s too early for us to be happy. Scientists can’t really determine whether the ninth planet exists. Although the abnormal orbits of some celestial bodies at the edge of the solar system do tell us that there is a huge gravitational source there, it’s still unknown whether this gravitational source is a planet.
In addition to planets, there is another kind of celestial body that can also cause a huge gravitational effect, and it is more hidden and difficult to be found. This kind of celestial body is the most mysterious and powerful black hole in the universe. I believe my friends all know that it is a kind of celestial body in Einstein’s theory of relativity conjecture in the last century. Now the existence of black holes has been confirmed, and scientists have released the first pictures of human black holes.
Black holes can be divided into many kinds according to their mass. The smallest one is the primary black hole. Although it is small, its mass is equivalent to that of a super earth, which will produce huge gravitational effect. Some scientists speculate that this huge gravitational source at the edge of the solar system may be such a primary black hole.
If the ninth planet is really a very small primary black hole, it will be even more difficult for us to find it. To know the powerful phagocytic characteristics of black holes, even light can be phagocytized, so we can not directly observe the existence of black holes. However, when a massive black hole devours a huge celestial body, it will form a bright accretion disk. We can definitely find the black hole through the accretion disk.
But if they are black holes with very small mass, they will not have accretion disks, so it is impossible for optical telescopes to observe them. Of course, scientists are not completely disappointed. Although black holes are more hidden, they still have a way to observe their powerful special ability.
Black hole has a strong radiation ability. If the gravitational source at the edge of the solar system is really a black hole, it will release some special radiation of black hole. As long as we can detect some unusual radiation, there may be hope to find it. Scientists are more interested in black holes than in a planet.
If the ninth planet is really a black hole, it will be of great significance to human beings, and we may be able to reveal part of the mystery of the black hole through it. As the most mysterious and powerful celestial body in the universe, black hole may be related to some ultimate mysteries of the universe. To understand it is to really understand the universe. We look forward to one day when scientists can really understand whether there is the ninth largest planet on the edge of the solar system and its true features.