Hey guys! I am sure that you would be knowing about the "blue planet" as you live on it but you must not be knowing that from where this "blue" water come on earth? Let's find out -
Earth's water is rare but the universe is full of water clouds ! Then how water on earth is rare? Before we begin our journey to expose the blue planet you should know that every type of water in this universe has its own chemical signature (chemical signature means that molecular structure of any compound) and among all of them chemical signature of water on earth (H20) is very rare.
In earth's water in every 10,000th drop of water one drop is of semi heavy water (a water molecule having one electron, one proton plus one neutron ) This signature is very rare.
Earth is blue as it has abundant of water on its surface. There are many conflicting views that how earth became "blue" . Let's discuss them one by one.
It was believed that asteroids could fill earth surface with water during the late heavy bombardment period (approximately 3.8 to 4.1 billion years ago) Initially, in astrophysics asteroids were called dry rock . They were believed to have no water. But when a big asteroid (Bennu) was studied carefully when it arrived near the earth, it seemed to have some liquid water. When scientists did research on it under the OSIRIS-REx mission of NASA they came to know that it has water content of approximately 1 million ton gallons of water and more astonishingly the chemical signature of water on Bennu and Vesta was very similar to that of our earth's. This research changed their idea about an asteroid and they began thinking "Were asteroids the asteroid responsible for the abundance of water on earth?" But one strange activity deep beneath the earth (in earth's mantle) answers their questions in "No". Scientists observed that the seismic waves coming from in between of outer core and inner mantle were absorbed or interrupted by something present deep beneath the earth's surface. They detected that there is a large amount of water in the earth's mantle. The water present in the mantle can twice fill all water bodies present on earth. This discovery made scientists think that asteroids were not responsible for the "the blue " color of our earth as asteroids couldn’t reach the mantle of our earth to deliver water. Something mixed the clouds of water (h2o ) into the moving disc of gas and dust in our nursery moving around the sun. But what and how.......
Scientists on NASA's OSIRIS-REx mission proved shortly after arrival at this near-Earth asteroid, called Bennu, that it carries hydrated minerals.
(Image: © NASA/Goddard/University of Arizona)
2. You would have thought that if asteroids are suspected to bring water on earth then can't comets be suspected? No doubt comets have water but a little as compared to asteroids. Moreover, water on comets has a completely different chemical signature so comets cut down from the list.
3. ......the answer is Jupiter, the gas giant.
Jupiter was made at the position where today Neptune is. Jupiter brought a chunk of large cloud of H2o 4.6 billion years ago from the Kuiper belt(snow line)and it was mixed in the clouds of the inner asteroid belt what as we call it today. This is the only time when planets like Earth, Mars, Venus were being formed. The making of Mars and Venus with our planet Earth with the water-rich cloud ( brought by Jupiter ) made earth blue.
Then what happened to the water of Venus and Mars? About Mars, you can read here and For Venus, the blog is here.
Watch here:-Earth's water