Those rings of dust may have prevented Earth from growing into a "super-Earth."
According to the simulations, the nearest ring to the sun formed the planets of the inner solar system — Mercury, Venus, Earth and Mars. The middle ring would ultimately become the planets of the outer solar system, while the outermost ring formed the comets, asteroids and other small bodies in the Kuiper Belt, the region beyond the orbit of Neptune.
https://www.livescience.com/baby-sun...gs-like-saturn