Why does the Sun contain more than 99 percent of the solar system’s mass?

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Illustration showing the eight planets of the solar system in order from the Sun-Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune-depicted to scale by size, with labeled diameters in miles and kilometers. The Sun is partially visible on the left for comparison. — Solar system The planets (in comparative size) in order of distance from the Sun.

The Sun contains more than 99 percent of the solar system’s mass because it formed as the central condensation of the solar nebula, a rotating disk of gas and dust that collapsed under its own gravity approximately 4.56 billion years ago.12

As this cloud collapsed, the vast majority of the available material was drawn into the center, where high pressures and densities eventually triggered nuclear fusion, giving birth to the Sun. The remaining material in the outer part of the disk, which accounts for less than 1 percent of the total mass, coalesced to form the planets and other smaller bodies, such as asteroids and comets.1234