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The solar system is home to the earth, and this galaxy has planets, asteroids and various comets. There are unequal numbers of planets in every star system, and the solar system is no exception. So how many planets are there in the solar system?
I believe that many of my friends will see the nine planets in the solar system in the books in the past. Yes, there were nine planets in the solar system in the past. However, there are only eight planets in the solar system. Why is that so? The reason is that Pluto was listed as a planet by scientists. Then why is Pluto being kicked out of the list of planets, is it because its mass is too small?
In fact, the reason why scientists have kicked Pluto out of the list of planets is not because its mass is too small, but mainly because scientists have redefined planets. In the third clause of the new definition, it requires the line to be able to clear its orbit, which means that the planet should dominate the orbit. According to this standard, Pluto is obviously not in compliance, because its orbit is not clean, and some celestial bodies still exist.
After Pluto was kicked out of the nine planets, the solar system became eight planets. For many old friends, this change is still unacceptable. We must know that the theory of the nine planets has been extended by mankind for more than thousands of years, and nine is a very important number in human civilization. Therefore, many people still hope that one day, the solar system can return to the theory of nine planets.
Is it possible to realize such a wish? If you want Pluto to return to the list of planets, don’t think about it, because with the continuous improvement of human understanding of the universe, Pluto obviously does not meet the standards of planets. If Pluto cannot return to the list of planets, is there a ninth planet in the solar system?
I believe that in recent years, many friends have heard of the conjecture proposed by scientists about Planet Nine. Why do scientists have such speculations? In fact, it is related to some research findings of scientists in the solar system. In 2016, Constantine Battykin and Mike Brown of the California Institute of Technology announced the discovery of a group of very distant extra-Neptune objects (TNOs). The way is clustered together, and the tracks are very similar.
Their orbits are all oddly inclined, as if they all interact with a larger planetary body gravitationally. But there are no known large planets in this area. So Batykin and Brown speculated that there might be an undiscovered planet there. So the search for Planet Nine began.
It can be seen from this that scientists did not make any unfounded guesses about Planet Nine, but made judgments based on the abnormal orbits of some celestial bodies found at the edge of the solar system. We all know that gravitation exists between celestial bodies in the universe. The greater the mass of the celestial body, the stronger the gravitational force, which will have a more obvious impact on the celestial bodies in Zhou.
According to scientists’ guesses, the ninth planet at the edge of the solar system, if it exists, has a mass 5-10 times that of the Earth. Such a planet can be regarded as a super-Earth. If such a huge planet exists at the edge of the solar system, the gravitational force generated by it will inevitably have a significant gravitational influence on many surrounding celestial bodies.
Of course, it is not easy to find Planet Nine. The edge of the solar system is a blind spot for human exploration, where the light is very dim. Even so, scientists believe that if such a huge planet exists, it should emit infrared radiation, which is the energy that has been leaking outward since the planet was formed. As long as the planet has infrared radiation, writers should find something that day with the help of infrared detection methods.
But until now, apart from causing gravitational effects in the outer solar system, scientists have found almost no direct evidence of its existence. Doesn’t Planet Nine exist? But if it does not exist, how can the anomalies in the orbits of celestial bodies discovered by scientists at the edge of the solar system explain? Since the orbits of these very distant celestial bodies outside Neptune are abnormal, it means that there must be a huge source of gravity here.
If this huge source of gravity was not a planet, what would it be? At this time, some scientists thought of black holes. On September 24, 2019, astronomer Jakub Scholtz of Durham University in the United Kingdom and James Enwin of the University of Illinois in Chicago published a new study describing They put forward another hypothesis for the peculiar gravitational phenomenon in the outermost layer of the solar system. They believe that these strange phenomena may not be caused by a planet at all, but may be a primordial black hole. After the theory was published, it caused some controversy.
The so-called primordial black hole is actually a small-mass black hole formed immediately after the Big Bang. The density fluctuations in the early universe can quickly form black holes of different masses. These ancient celestial bodies will move around in the universe. As time goes by, they will slowly evaporate through Hawking radiation, and the smaller black holes will disappear first.
Although there are many cosmological evolution theories that the original black holes should exist, we have not directly observed them. Such black holes are too small to pose a threat to other areas of the solar system. But in the remote areas of the solar system, its impact is huge.
Black holes are completely different from other celestial bodies. We all know that black holes have a powerful ability to swallow, and even light enters the black hole and cannot escape. If it is a planet, it can emit infrared radiation, and we may find it possible with optical and infrared observations. But if this is a black hole, our optical and infrared observation methods are useless. It is a completely hidden existence.
Moreover, the mass of the original black hole is relatively small, and there will be no bright accretion disk around it, so even if it is right in front of us, we cannot see it. Is there no way for us to detect this possible primordial black hole? Of course not. If this black hole is outside the solar system and is far away from us, then we will have nothing to do.
We can observe some black holes outside the solar system, mainly because of those supermassive black holes, which have very bright accretion disks and can emit various intense radiations. We can know that there is a supermassive presence there by observing these strong energy radiations. Black holes, such as the center of the Milky Way.
But now this small-mass black hole is at the edge of the solar system, not too far away from us, so as long as it is carefully searched, there may still be hope for observation and discovery. It’s just that infrared observations and optical observations are impossible to discover the existence of this small black hole. What we can use is moving X-rays, gamma rays and other high-energy cosmic rays to conduct a detailed search.
Although a black hole has a powerful ability to swallow, even light will not be let go, but a black hole is not a celestial body that can only swallow it. According to the Hawking radiation theory, it still releases some energy, but the energy needs more Only powerful detection equipment can find it, and it must be very close to us.
Regardless of the existence of Planet 9 on the edge of the solar system, some celestial orbital anomalies tell us that there is a high probability that there is a huge source of gravitation. Even if it is not a planet, it may be a black hole or other unknown existence. For current human technology, we can only detect this huge gravitational object at the edge of the solar system through astronomical telescope and other observation equipment.
Someone might say that we can send a spacecraft to the solar system for detailed observations. If there is really Planet Nine there, wouldn’t it be easier to find it? In fact, this method is not advisable with the current technological strength of mankind. We must know that if Planet 9 really exists, its orbital period will reach 10,000 to 20,000 years.
Moreover, the universe is a three-dimensional space. If we do not have definite coordinate information, it may be many times more difficult than finding a needle in a haystack if the spacecraft heads to the edge of the solar system and wants to meet Planet Nine. In fact, one of the more important reasons why scientists did not send spacecraft to the edge of the solar system to search for Planet 9 is that the speed of the spacecraft is too slow.
If we now have the ability to fly at sub-light speeds, and it only takes a few hours for the spacecraft to depart from the earth to the edge of the solar system, it will naturally be very simple to search for Planet Nine. We can use the spacecraft to carpet the edge of the solar system. Search. If Planet Nine really exists, it will naturally not be able to escape the spacecraft’s search. Even if it is an invisible primordial black hole, once the spacecraft approaches unintentionally, its strong gravity will have a very obvious impact on the spacecraft. At that time, we naturally know where it is.
This shows that we are now entangled in whether it is a planet or a primordial black hole. The main reason is that human beings have limited scientific and technological capabilities, and there is no more powerful detection method to truly search for the edge of the solar system. Of course, as long as we continue to work hard and believe that in the near future, this mysterious source of gravity at the edge of the solar system will be exposed, and the truth about whether it is a planet or a black hole will become clear.