If we knew a hundred years in advance that a giant planet was going to hit the Earth, could humans survive?

An International Planetary Defense Conference is held every two years in the world. During the five days of the conference, hundreds of scientists from all over the world will try to prevent an asteroid from hitting the earth. Of course, this incoming asteroid is just a topic and does not really exist.

So, can humans today save the Earth from the threat of asteroids? Well, although humans are not sure that they can deal with the threat of asteroids without any damage, they can definitely save humans from annihilation. So, what if it is not an asteroid but a giant planet? Giant planets and asteroids are completely different things. The asteroids we usually talk about are mostly tens to hundreds of meters in diameter. The diameter of Apophis, which was once thought to be quite threatening to the Earth, is about 400 meters.

If a giant planet is likened to a watermelon, then an asteroid is not even as big as a sesame seed.

There are 8 planets in the solar system, and the four closest to the sun are rocky planets, namely Mercury, Venus, Earth and Mars. The Earth is the largest, with a diameter of 12,740 kilometers, but it is still far from being a giant planet. Who are the giant planets? They are the four planets on the outer edge of the solar system, Jupiter, Saturn, Uranus and Neptune. Uranus and Neptune are ice giants, while Jupiter and Saturn are larger gas giants. Among the four, Jupiter has the largest mass and volume. There is no doubt that Jupiter is a typical giant planet. Its mass is more than twice the total mass of the other seven planets. Compared with the Earth, its mass is 318 times that of the Earth and its volume is more than 1,300 times that of the Earth.

If Jupiter is compared to a watermelon, then the Earth is probably a grape, oh no, a raisin.

Obviously, if such a huge planet hits the Earth, it will inevitably engulf the Earth, not to mention the creatures on Earth, even the Earth itself will cease to exist. So, if we can know a hundred years in advance that a giant planet is coming towards the Earth, will humans be able to survive? Whether it is Jupiter, Saturn, Uranus or Neptune, they will not hit the Earth, because they all have their own stable orbits and run stably under the gravitational force of the sun. But in the universe, not all planets have stable orbits. Some planets have deviated from their original orbits for various reasons, drifting in the universe and becoming wandering planets.

There are many wandering planets in the universe, and it is not impossible that one of them is so blind as to head towards the Earth. Fortunately, giant planets are very large, so it is easy for us to discover them, and a hundred years in advance is not a problem.

The problem is that 100 years in advance is actually too late. The speeds of planets in the universe vary. For example, the Earth's orbital speed is about 29.8 kilometers per second, while in the universe, some planets can move at speeds of tens of thousands of kilometers per second, or even hundreds of thousands of kilometers per second. Even if a planet is heading for the Earth at 200,000 kilometers per second, discovering it a year in advance means that the planet has already entered the solar system, because the radius of the solar system is 1 light year. What should we do at this time? It is impossible to change the orbit of a giant planet with current human technology, so we can only run.

Where did they go? To other planets in the solar system?

No habitable planets other than Earth have been found in the solar system. Of course, we can first concentrate global forces to build a base on Mars, migrate a small number of people to this base, and leave a spark of hope for the continuation of human civilization. Although this is not an easy task with the current capabilities of human beings, it can be completed in a hundred years if resources are concentrated. Unfortunately, even if we do it, it will be useless. A giant planet hitting the Earth is indeed a terrible thing, but even if it does not collide with the Earth, its invasion of the solar system itself is a terrible thing, because the intrusion of a giant planet will completely disrupt the gravitational structure of the solar system.

The solar system was not as stable and orderly as it is now from the beginning.

It has experienced countless planetary collisions and mergers to become what it is today. If a giant planet breaks into the solar system, it will make the solar system chaotic again. The small celestial body will be the first to break away from orbit and crash into other planets, so before the giant planet approaches, the earth may be hit by meteorites. What's more terrifying is that other planets will also be in chaos, so before the giant planet hits, the earth may collide with Mars. After the entire solar system has become chaotic, it is impossible to determine where it is safe, so even if bases are established on other planets, humans will not be able to survive. Fortunately, all of this is just a hypothesis, and humans still have enough time to realize their interstellar dreams. Maybe one day we will really be able to leave the solar system.

For more information, please follow the official account: sunmonarch