From Cosmic Dust to Living Planet: Re-evaluating Earth's Genesis, Ocean Formation, and Dynamic Hydrology

A pervasive misconception in popular science asserts that Planet Earth originated as a severed molten fragment ejected directly from the Sun. Modern astrophysical and geological evidence definitively refutes this solar-ejection hypothesis. This paper presents a comprehensive review of Earth's true evolutionary trajectory: beginning with its accretion from circumstellar dust particles within the Solar Nebula ~4.6 billion years ago, transitioning into a primordial global magma ocean, and subsequently cooling into a water-dominated primordial world. it examines the mechanisms of plate tectonics that uplifted continental landmasses and carved oceanic basins, establishing the modern ~71% to ~29% ocean-to-land ratio. Additionally, this paper quantitatively evaluates planetary mass balances to address common hydrological queries—demonstrating why total biological water content is negligible compared to oceanic volume, and clarifying that contemporary sea-level rise is driven by thermal expansion and cryospheric degradation rather than biological inputs.