Mystery: Where did the water on earth come from?
As you may already know, about 70% of the planet's surface is covered by water. However, did you know that even today scientists are not sure how all this water ended up here? After all, the current consensus is that the formation of our planet began about 100 million years after the origin of the Solar System and came about from a series of particle collisions - which were gradually aggregating.
Then larger bodies began crashing into our emerging world, adding volume to the planet. Moreover, in the early days of its existence, the earth was still bombarded by the scorching heat of the - then younger and more vigorous - sun and was then a huge sphere of lava.
In the world it was once a very unfriendly place
However, when the earth began to cool, the magma turned to rock, the water began to condense, and eventually its consolidation took place some 4.5 billion years ago. Throughout this time, the planet has been transforming itself into this incredible and livable place that is home to all of us. But what about water? Where did she come from?
According to Kristina Grifantini of the Live Science portal, many scientists believe that any water that had accumulated on the earth's surface during its formation 4.5 billion years ago would have evaporated because of the sun's action. water must not have come to our planet while it was forming, but it probably got here by hitchhiking on celestial bodies that traveled through the Solar System and collided with us.
Had the water hitched a ride on a comet tail?
This is because our closest neighbors - Mercury, Mars and Venus - also did not have the ideal conditions for water formation in the early Solar System, so the liquid must have come from somewhere else. One of the ideas is that water was brought by comets, for example, whose bodies almost always consist of rocks and large ice fragments.
The problem with this theory is that, after analyzing the tails of some of the major comets orbiting the sun - such as Halley, Hale-Boop and Hyakutake - scientists have found that the composition of ice is different from that of water that exists on the planet. Thus, another theory that has gained strength in recent years is that water may have come from the asteroid belt.
Would this be its origin?
The asteroid belt is a region of the Solar System that lies between the orbits of Mars and Jupiter and houses billions of rock and metal bodies of different sizes. For until recently, astronomers thought that this strip of debris was too close to the sun for water to exist there.
Planet - Almost All - Blue
However, scientists have found evidence of ice on an asteroid called 24 Themis, suggesting that this material may be much more abundant in the belt than previously thought. Luckily, the discovery has opened yet another range of possibilities for astronomers to explore, and perhaps one day they might unravel this mystery for good!