Have you ever looked at a globe and marveled at how much of our planet is covered in water? It's truly fascinating to consider that about 71% of the Earth is water! But how did earth get water? Let's dive in and find out.

How Did Earth Get Water? Theories and Insights

The exact origin of Earth's water still proves to be a conundrum that continues to baffle scientists and researchers today. There are, however, two prominent theories postulated, each with their respective weight of validity.

  1. Comet or Asteroid Impact: This theory suggests that the Earth's water came from comets or asteroids striking the Earth's surface. These celestial bodies, composed of icy compounds, could have potentially delivered water upon impact.
  2. Outgassing from the Earth's Interior: Another proposal is that Earth's water came from the planet's interior, escaping to the surface as steam via volcanic eruptions.
    Although each theory has its merits, it's most likely that our planet's water came from a combination of both.

Comet or Asteroid Impact - A Heavenly Gift

Many scientists believe that water arrived here from outer space. Early in the Earth’s history, our planet was in a molten state, making it virtually impossible for water to exist. The vast oceans and lakes we have today could have come from ice-laden comets and asteroids that collided with the Earth, depositing their precious cargo.
Are you wondering how much impact it would take to create our oceans? Well, a whole lot! It's calculated that it would require the impact of at least a billion comets or asteroids to create the volume of water present on Earth today.

Outgassing - The Earth's Hidden Treasure

On the other hand, another school of thought suggests that water has always been part of the Earth's composition. The water might have just been trapped beneath the Earth's crust and was released over time through volcanic activity. This process is known as outgassing.
In fact, outgassing still contributes to the Earth's water content even today, as geothermal activity continues to release steam into the atmosphere.

Conclusion - A Confluence of Sources

So, how did Earth get water? It’s most likely a combination of both external and internal factors. Astoundingly, the water we drink today might well have existed in the frozen heart of a comet or sequestered deep within the Earth's crust for billions of years. Isn't it mind-boggling when you consider the epic journey your glass of water might have made to reach you?
The mystery of how Earth got its water is still an ongoing exploration. And as we continue to appreciate this precious resource and its incredible journey, understanding its origins encourage us to treasure and protect it more.


Explore the fascinating theories behind how the Earth got its water - Was it a celestial delivery, or a treasure from within the depths of the Earth's crust? Discover the origin of this essential life-sustaining fluid.