Other Free Encyclopedias » Science Encyclopedia » Science & Philosophy: Nicotinamide adenine dinucleotide phosphate (NADP) to Ockham's razor » Ocean - Origin Of Ocean Water, Lithospheric Plates And The Origin Of The Seafloor, Weather Effects Of Ocean Waters - Hydrologic cycle

Ocean - Origin Of Ocean Water

earth planet surface molten

As Earth formed in a cloud of gas and dust more than 4.5 billion years ago, a huge amount of lighter elements, including hydrogen (H) and oxygen (O), became trapped inside the planet as the gases condensed and formed molten rock. Materials of different densities separated out; in the young planet's molten interior, heavy elements sank and light elements rose.

Gases rose through thousands of miles of molten and melting rock, to erupt on the surface through volcanoes and fissures.

Within the planet and above the surface, oxygen combined with hydrogen to form water (H20). Enormous quantities of water—enough to fill oceans if it were liquid—shrouded the globe as an incredibly dense atmosphere of water vapor. Near the top of the atmosphere, where heat could be lost to outer space, water vapor condensed to liquid and fell back into the water vapor layer below, cooling the layer. This atmospheric cooling process continued until the first raindrops fell to Earth's surface and flashed into steam.

Many geologists argue this process may have happened several times, because planetoids (rocks the size of moons or asteroids) were still colliding with the early earth until about 3.9 billion years ago. Monstrous planetoid impacts would have vaporized all the water on the planet's surface. Earth has been changed so much by plate tectonics that no vestige of its original appearance remains. Unlike Earth, the faces of the moon, Mars, and Mercury bear the marks of the turbulent earliest history of the solar system. Hellas Basin on Mars and Caloris Basin on Mercury are the scars of planet-shattering impacts. One of these giant craters can be seen from anywhere on Earth: the moon's large round dark "eye," called Mare Imbrium.

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almost 6 years ago

tanks men.......dats valuable info

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over 6 years ago

this is useful information... im an 8th grader doing a project and i needed information on the origin of the ocean on earth's planet... @ jake you need information and proof to prove your hypothesis right... hence, ever tried more research. Moreover, thank you for printing all this information :] please keep on with your research.

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almost 8 years ago

Water exists on both venus and mars but mostly as vapor on venus and as ice on mars due to temperature.
Venus is closer to the sun and hence starts off hotter while Mars is further away and hence starts off colder.
The earth's Moon is very large compared to the moons of Venus and Mars. The Moon stabilized the Earth's rotation and hence its climate.
The Earth has a liquid core, the rotation of which creates its magnetic field. The magnetic field deflects many charged particles that would otherwise interact with the atmosphere and tend to burn it off.
Venus likely has a liquid core but it rotates very slowly so it would have a correspondingly smaller magnetic field. Mars is smaller and does not have a large liquid core and so no magnetic field.

So it appears that the Earth's unique distance from the Sun, its size and its proportionately large moon have a lot to do with things.

Some believe that the earth's size and position coupled with Jupiter's attraction of the largest impacts allowed for comets and asteroids to impact the earth more gently, adding to the tendency for the earth to retain the water brought to us by these objects. Again, there is much disagreement as to how much of earth's water is of an external origin.

One thing is sure and that is that presently, earth's temperature, its magnetic field and its atmosphere are the 3 main reasons that water can exist here in all three phases (solid,liquid,gas) whereas it exists in only one phase on both venus and on mars.

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almost 9 years ago

thnx 4 they info.. now i can start my report.. god bless...

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almost 9 years ago

that was helpful...now i need the origin of the atmoshpere

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almost 10 years ago

wow that explains it, but why don't we see water on any other planet?