Here's a more detailed explanation of the theory:
1. Early Earth Formation: During the early stages of Earth's formation, it was a hot and molten ball. The intense heat vaporized any water present on the planet, preventing the formation of oceans.
2. Accretion of Comets and Asteroids: As Earth orbited the Sun, it collided with numerous comets and asteroids that were leftover debris from the protoplanetary disk. These icy objects contained a significant amount of water in the form of ice.
3. Water Delivery: Upon impact, these comets and asteroids released their water content into Earth's atmosphere. As the atmosphere cooled down over time, the water vapor condensed and fell as rain, contributing to the formation of Earth's oceans and other water bodies.
4. Accumulation and Hydrosphere Formation: Over billions of years, the continuous bombardment of comets and asteroids along with other geological processes led to the accumulation of vast amounts of water on Earth. This water accumulated in low-lying areas, forming oceans, lakes, rivers, and other bodies of water, thus creating the Earth's hydrosphere.
It's worth noting that while the comet and asteroid theory is the leading explanation, there are other hypotheses suggesting different mechanisms for water delivery to Earth. These theories include the formation of water from volcanic eruptions, the capture of water from the solar nebula, and the contribution from micrometeorites and interplanetary dust particles.
The study of water's origin on Earth is a complex field of research, and scientists continue to investigate various aspects to gain a better understanding of how our planet acquired the water that sustains life.
