'Planet 9' left its mark on Earth before disappearing?

A mysterious planet may have approached the early Sun at a distance slightly farther than Uranus and rearranged everything in the star system.

According to a new study led by Dr. Garett Brown from the University of Toronto (Canada), in addition to the eight current planets, there was once another planet in the solar system that was 2-50 times the size of Jupiter.

But that giant did not come from the Sun's protoplanetary disk, but was an invader.

An invading planet may have approached the Sun at a distance just a little farther than Uranus - (AI illustration: Thu Anh).

According to Science Alert, the research of Dr. Brown and his colleagues has investigated how a planet visiting the Solar System in the past can shape the orbits of objects today, including Earth.

Calculations put the likelihood at 1 in 100, a significant fraction of the impact it could have.

Using simulations, they calculated the enormous size of this visitor, and showed that it approached the Sun at a very close distance of up to 20 astronomical units (AU) , which is as far as outside the orbit of Uranus.

One AU is equal to the distance from the Sun to Earth, and Uranus is about 19 AU from the Sun.

For distances between objects not in the same star system, passing by each other at only 20 AU is too close.

The idea for this study comes from an effort to study the orbital evolution of planets in the Solar System, which is still full of holes.

The evolution of planetary orbits is a complex process, with each planet today no longer in its original orbit.

Of these, Jupiter and its movements are believed to have had the greatest impact on shaping the orbits of the planets today. However, this alone cannot explain all the complexities and differences in the orbits of the other seven planets.

The aforementioned giant invading planet provided another piece of the puzzle, filling in some gaps.

In addition, the above results also help us understand more about strange visitors that can enter the heliosphere.

Thanks to modern observation techniques, humans have captured several strange visitors from the interstellar medium in recent years, although they were only asteroids.

The most famous of these is Oumuamua, an asteroid with a cigar shape and an odd orbit, suspected by some scientists from Harvard University (USA) to be related to alien technology.