Validation of the Protoplanetary Theory of Solar System Formation

Abstract

Kant’s 1755 hypothesis on the origin of the sun and planets, as modified by Laplace, foreshadowed the modern protoplanetary theory of planet formation in which planets were thought to form at very high pressures from within giant gaseous protoplanets. The protoplanetary theory was popular in the 1940s and 1950s, but was abandoned and ignored by phenomenological model-makers in the early 1960s who favored the planetesimal theory, the idea that planets formed by the progressive accumulation of dust that had condensed at very low pressures. Here, I validated the protoplanetary theory by: • Thermodynamic considerations; • Observations of internal magnetic field generation; • Observations of Mercury; and, • Observations of Earth’s behavior. Although the planetesimal theory did not account for solar system formation, some of its elements added a veneer of oxidized material to the outer portions of Earth, especially oxidized iron which is critical for the development of life.