According to present-day scientific research, the Earth and the Sun were formed basically at the same time, gradually during the formation of the solar system. According to the hypothesis that the solar system originated from a primordial nebula in the Milky Way, the original material of the Earth also originated from the primordial nebula. The primordial nebula is mainly composed of gas, with very little solid matter, and if calculated by mass, gas accounts for about 98%. Among the gaseous substances, hydrogen and helium are absolutely dominant. Today, hydrogen and helium account for 77.2% and 20.9% of the universe, respectively, and they also account for 70% and 20% of the solar system, so it is clear that our universe is a world of hydrogen and helium. The original material on the Earth originated from the cosmic nebula, but the composition of the present-day cosmic material is so different from that of the nebula that the proportion of hydrogen and helium on the Earth is less than 1%, and almost no trace of nebular material can be seen.

At the very beginning of the Earth's formation, there was a process of accretion of starlets, which are small clumps of particulate matter in nebulae that are gravitationally attracted to each other, in fact, these starlets are meteoroids. The stars are then attracted to each other, and the larger stars "eat" the smaller ones, continuously colliding, accreting, and increasing in size until the Earth is formed. In fact, the process of star accretion to form the Earth is a meteorite impact process, so in the initial stage of the formation of the Earth, meteorite impacts are very frequent.

In the solar system, the material composition of different planets differs greatly, like Mercury, Venus, Earth, and Mars, their material composition is relatively similar, they are mainly composed of solid rocky material, they are called Earth-like planets, in the inner circle of the solar system. Jupiter and Saturn, on the other hand, are gas-based and are called Jupiter-like planets, which are in the outer solar system. In addition, of course, Uranus and Neptune are also included, but they differ significantly from Jupiter and Saturn in their material composition. Although these planets have the same origin, the formation of the present-day planets with completely different material composition is closely related to the evolution of the solar system. Some of the lighter gaseous material spreads outward during the rotation of the solar system and accumulates in the outer ring of the solar system to form the Jupiter-like planets, while the heavier solid material does not spread as easily and accumulates in the inner ring to form the Earth-like planets.

Meteorites also have a "twin sister" - meteorite ice. Meteorite ice is the surface of the comet nucleus spattered some broken ice, its composition is mainly water ice material, interspersed with some dust material. Like meteorites, meteorite ice was originally a "genie" that wandered in space and revolved around the sun, but sometimes they were forced to change their orbits and fall to the ground when they inadvertently entered the Earth's "trap". But meteorite ice is much rarer than meteorites, and its appearance is so similar to meteorites that if it is not found in time and preserved properly, it may remain anonymous and unrecognized, and thus very little meteorite ice has been identified until the 20th century.

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