Water on Earth predominantly arrived as vapour mixed with cosmic dust during the planet's formation, later cooling to create oceans and other water bodies.
While the fundamental chemical reaction creating a water molecule (H₂O) involves hydrogen and oxygen, the question of how water became abundant on Earth is a key aspect of planetary science. Based on the provided information, the process centers on the delivery of water to the early Earth and its subsequent transformation into liquid form.
The Cosmic Delivery of Earth's Water
- Current scientific understanding, supported by the reference, suggests that a significant portion of Earth's water was not initially present in its liquid state during the planet's formation.
- Instead, "The water formed was mostly in the form of vapour and got mixed with the cosmic dust to reach the surface of the earth."
- This indicates that water, already formed elsewhere in the cosmos, was transported to the nascent Earth primarily as a gas (vapour) carried within or alongside the rocky and icy materials (cosmic dust) that coalesced to build the planet.
Cooling and Condensation: Forming Oceans
- During Earth's early, hot stages, incoming water remained as vapour, contributing to a steamy atmosphere.
- As the planet gradually cooled over vast periods, the atmospheric water vapour reached temperatures where it could condense back into liquid form.
- The reference explicitly states this transformation: "When earth was formed, these water vapours cooled down to form oceans, seas, rivers lakes and other water bodies."
- This condensation likely resulted in torrential, long-lasting rainfalls that gradually filled the planet's basins, leading to the formation of the global oceans and other surface water features crucial for geological processes and the emergence of life.
Key Stages of Earth's Water Establishment
- Arrival: Water arrives on early Earth predominantly as vapour.
- Transport: Carried alongside or within cosmic dust and other materials.
- Accretion: Mixes with the matter forming the planet's surface.
- Cooling: Earth's surface and atmosphere cool down.
- Condensation: Water vapour transforms into liquid water.
- Formation of Bodies: Oceans, seas, rivers, and lakes are formed.
In summary, the presence of vast amounts of liquid water on Earth is a result of water being delivered to the planet during its formation phase, predominantly as vapour mixed with cosmic dust, followed by a crucial period of cooling that allowed this vapour to condense and accumulate into the familiar water bodies that define our world.
