A study by Rice University in the United States shows that before the formation of Earth and other planets in the solar system, the sun may have a huge dust ring similar to Saturn . Astronomers believe that these dust rings may have promoted the birth of the Earth, but also prevented it from growing into the so-called super-Earth (large rocky planet with a radius of about twice the Earth and a mass of 10 times the Earth).
Astronomers found that in Milky Way , 30% of star system , similar to the solar system, exists in super-earth. So, since the super earth is so common, why not in the solar system? So, astronomers at Rice University started their research from this question.
They used computers to create a model formed in the early stages of the solar system. Both the sun and the planet were born in a huge nebula called Sun Nebula .
As the sun forms, the surrounding dust is gradually attracted by the sun's gravity and approaches the sun. The heat causes the dust to release a large amount of gas and condense into three belts that look like dust rings surrounding the sun. The circle closest to the sun is vaporized silicate, the second circle is water macroqi, and the outer circle is carbon monoxide . These bands are like barriers that block the passage of dust, so companion star forms different bands, limiting the resources required for planetary growth.
As time goes by, the gas and dust around the sun gradually cool down, and the bands gradually approach the sun under the action of gravity. In this process, dust collides with each other, gathers into planets "seeds", and then grows into planets step by step.
Mercury, Venus, Earth and Mars was born in the belt closest to the sun, Jupiter , Saturn, Uranus and Neptune were born in the second belt, and the outermost belt formed the Kuiper belt, with many asteroids and comet in the belt.
Astronomers found that if the gas disk around the sun does not form a band, the sun will quickly swallow up the surrounding matter. The planet cannot be born. Furthermore, if the formation of the second belt is delayed, the earth may also grow into a super earth. Therefore, the time of the formation of the second zone may be a key to the evolution of the solar system.
(excerpted from the popular science magazine "Singularity Science" 2023 magazine subscription https://www.zazhipu.com/)
