Earth shouldn't exist: scientists discovered a strange cosmic symmetry that gave mankind a chance
The planets of the terrestrial group (or inner planets) of the solar system-Mercury, Venus, Earth, and Mars-should have collided with each other due to wandering through space, but a mysterious force keeps them from this catastrophe. Such collisions do not occur, although scientific models, which take into account the chaotic nature of planetary orbits, suggest that the catastrophe should have happened long ago.
This is according to a study published in the journal Physical Review X. Scientists decided to figure out what kind of force keeps planets from colliding.
After analyzing the motion patterns of the four planets, the researchers found that there are certain constraints that act as bindings and restrain the chaos of the system.
As scientists explain, the planets of the solar system are in constant interaction with each other due to the gravitational pull that exists between them. It is this gravity that makes constant adjustments to the orbits of the planets. For example, the outer planets of the solar system - Jupiter, Saturn, Uranus and Neptune - are too big and do not respond to small shocks caused by gravitational pull, so they maintain relatively stable orbits.
The trajectories of the inner planets are so confusing that it is impossible to calculate them. Back in the late 19th century, the mathematician Henri Poincaré proved the mathematical impossibility of solving an equation describing the motion of three or more interacting objects. This is commonly known as the "three-body problem.
As he found, even a minimal difference in the distances between the four inner planets in one of the variants would cause the planets to continue their cosmic dance, while in the other, they would crash into each other.
Subsequently, the concept of Lyapunov time was derived. This is the time in which two trajectories with almost identical initial conditions will diverge by a certain amount. In 1989, the astronomer and scientific director of the National Center for Scientific Research and the Paris Observatory and co-author of the new study Jacques Lascar calculated that the Lyapunov time for the orbits of the planets of the inner solar system is only 5 million years.
"In essence, that means you lose one digit every 10 million years," Laskar explained in an interview with Live Science.
For example, if the initial uncertainty of a planet's position is 15 meters, in 10 million years that uncertainty will reach 150 meters, and in 100 million years it will be 150 million kilometers, which is equivalent to the distance between the Earth and the Sun.
"Basically, you have no idea where the planet is," Laskar said.
In context, it's worth mentioning that the solar system is more than 4.5 billion years old, and the lack of collisions between planets in all that time seems strange, to say the least.
So Lascar and his colleagues created a new simulation that took into account the constraints that keep the motion of the planets within certain limits relative to their initial orbits. It turned out that the percentage of probability of a planetary collision fell to 1%. In order for such a catastrophe to occur, as calculated by scientists, it takes about 30 billion years.
Thus, scientists have actually managed to calculate a certain cosmic symmetry, which creates a "practical barrier to the chaotic wanderings of the planets.
Scientists stressed that this symmetry does not deprive the planets of chaotic motion, but only limits its magnitude, leading to the stability of the solar system.
Earlier OBOZREVATEL also told about what happens on Saturn that astronomers have never seen in the solar system.