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Thread: ORIGIN OF WATER ON EARTH

  1. #1 ORIGIN OF WATER ON EARTH 
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    ORIGIN OF WATER ON EARTH
    BY SUHAIL JALBOUT

    The planet Earth is the only planet in our solar system with huge amounts of surface water. It covers 70.8% of its surface. The estimated volume of all the existing water on Earth is about 1.33 billion cubic km. This is equivalent of having a water-sphere with a diameter of 1,366 km; the Moon has a diameter of 3,476 km, Pluto has a diameter of 2,360 km, and Chiron has a diameter of 1,172 km.

    There are many theories that explain the origin of water on the Earth. It is believed that the bombardment of comets, “wet” asteroids, and ice particles formed the major part of water on Earth. However, the main contributors are comets since 40% of their mass is water-ice. The average diameters of comets range from 1.0 km to 20 km. Let us assume that the comets that bombarded Earth are spherical in shape and of the same size with an average diameter of 10 km. Since 40% of their mass is water-ice, the amount of water that each comet will have is 209 billion tons. This means that the number of comets that should bombard Earth to produce the major part of Earth’s water is 6.36 million. If this quantity represents 0.1% of the total quantity of the comets that passed near Earth, then the total number of comets that should have existed is 6.36 billion comets. This is a huge unconceivable amount of comets that passed near Earth or fell on it before the oceans were formed. No doubt comets, “wet” asteroids, ice particles, volcanic eruptions, and water vapor in the original Earth’s atmosphere contributed to the formation of water on Earth. However, it does not sound feasible that they have produced alone the 1.33x10^18 tons of water on the planet. There must be another source that contributed to the major volume of water on Earth.

    I tend to believe that the solar system was formed in accordance to the “Nebular-Ripple Hypothesis”.[1] Rings were formed, in a geometric progression, around the equator of the Sun due to its push-pull forces. These rings were transformed into planets and each planet had its own rings. The rings of the planet that were outside the Roche limit formed moons. However, those within the Roche limit either remained to our present day or disappeared.

    The outside planets, Jupiter, Saturn, Uranus, and Neptune still have their rings. The rings of Mercury, Venus, Earth, and Mars vanished. The composition of the rings of Saturn and Uranus are mainly water-ice. If we assume that the original rings of the inner planets contained also water-ice, then it is possible to predict their disappearance. Those of Mercury and Venus were blown away in space due to solar heat and solar wind. The rings of Earth and Mars must have collapsed flooding both planets with water.

    The ring around Earth was experiencing two equal forces in opposite directions. The Earth was pulling the ring inwards while the Moon was pulling the ring outwards. It is quite possible that traces of the ring may have lasted to date if it was not for our Moon. The Moon is receding from Earth, at the present time, at a rate of 3.8 cm per year. It is believed that it was receding at a rate of 10 km per year when the Earth and Moon were created 4.6 billion years ago. Let us assume that the Moon was receding at an average rate of 5 cm per year during its life time. This means the Moon receded to date by 230,000 km. The Moon’s closest perigee, at the present time, is 365,000 km. Thus, the distance of the Moon from Earth was 135,000 km at the time of their creation.

    The theoretical calculated Roche limit is 2.5 times the radius of Earth. This means that the ring that was formed at the equator of Earth should have been located at a distance less than 16,000 km from the center of Earth. Let us assume that its average distance was 14,000 km.

    The oceans on Earth were formed about 1 billion years from the time of its creation. This means that the Moon had recessed by 50,000 km during this period.

    Using the above estimated numbers in very simplified mathematical equations gives the following result:

    The outward pull of the Moon on the ring, at the time when the oceans were formed, was 50% less than its outward pull when it was created. This reduction in the outward pull changed the ring’s distance from Earth and its angular momentum. As a result, the ring collapsed towards Earth. When the ring entered the Earth’s atmosphere, most of its water-ice melted due to friction. Water in huge amounts must have flooded a large belt around the Earth’s equator. From the equator water spread to the north and south poles flooding the Earth and creating oceans. We can thus conclude that the Earth received the major part of its water from the ring that was in orbit during a short period of time.

    What about Mars? According to NASA, Mars had oceans covering 30% of its surface. For some unknown reason, Mars lost its water.

    Most probably water was formed on Mars in the same way as water was formed on Earth. However, I believe Mars experienced a horrible catastrophe few billion years ago. The moons of Mars are not spherical. They are potato shaped. All moons that were formed at the time when the solar system was created are spherical in shape. Since the moons of Mars are not, this implies that a cataclysm happened to Mars and to the two moons. The culprit that caused the cataclysm is the explosion of Bode’s planet that existed between Mars and Jupiter at the time when the solar system was created, please refer to my theory “Reviving Bode’s Law”.[2] Huge asteroids from the smashed planet bombarded Mars and its two moons. The bombardment deformed the two moons, or possibly split the original one moon of Mars into two pieces, and evaporated all of Mars surface water.

    END NOTES

    [1] 2012forum.com › ... › Potential Threats › Other Space Nasties - Cached
    [1] www.thescienceforum.com/viewtopic.php?p=121754 - Cached
    [1] http://www.daviddarling.info/encyclo...nebhypoth.html
    [1] http://www.thunderbolts.info/tpod/2006/ ... solar4.htm
    [2] 2012forum.com › ... › Potential Threats › Planet X - Cached
    [2] www.thescienceforum.com/viewtopic.php?p=126215 - Cached


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  3. #2 Re: ORIGIN OF WATER ON EARTH 
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    Quote Originally Posted by Suhail Jalbout
    This means that the number of comets that should bombard Earth to produce the major part of Earth’s water is 6.36 million. If this quantity represents 0.1% of the total quantity of the comets that passed near Earth, then the total number of comets that should have existed is 6.36 billion comets. This is a huge unconceivable amount of comets that passed near Earth or fell on it before the oceans were formed.
    since estimates for the total number of comets in the solar system ranges from 10^11 to 10^12, two orders of magnitude more than your requirement, I see no problem with comets being the source of Earth's water. Your argument is an argument from incredulity and of no consequence.


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  4. #3 Re: ORIGIN OF WATER ON EARTH 
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    Quote Originally Posted by Ophiolite
    Quote Originally Posted by Suhail Jalbout
    This means that the number of comets that should bombard Earth to produce the major part of Earth’s water is 6.36 million. If this quantity represents 0.1% of the total quantity of the comets that passed near Earth, then the total number of comets that should have existed is 6.36 billion comets. This is a huge unconceivable amount of comets that passed near Earth or fell on it before the oceans were formed.
    since estimates for the total number of comets in the solar system ranges from 10^11 to 10^12, two orders of magnitude more than your requirement, I see no problem with comets being the source of Earth's water. Your argument is an argument from incredulity and of no consequence.
    This.
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    Ophiolite wrote: " I see no problem with the comets being the source of Earth's water."

    Let us assume that the required 6.36 million comets, with 10 km diameter each, bombarded Earth to produce its water. The impact of each comet on the surface of Earth will form a crater with an area of at least 78.54 km2. Assuming that the comets fell side by side, they will cover an area of 500 million km2. Since the surface area of Earth is 510 million km2, this means 98% of Earth’s surface would be covered with craters. With all my due respect to your thoughts, I doubt the view that comets had the upper hand in producing Earth’s water.
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    Quote Originally Posted by Suhail Jalbout
    Ophiolite wrote: " I see no problem with the comets being the source of Earth's water."

    Let us assume that the required 6.36 million comets, with 10 km diameter each, bombarded Earth to produce its water. The impact of each comet on the surface of Earth will form a crater with an area of at least 78.54 km2. Assuming that the comets fell side by side, they will cover an area of 500 million km2. Since the surface area of Earth is 510 million km2, this means 98% of Earth’s surface would be covered with craters. With all my due respect to your thoughts, I doubt the view that comets had the upper hand in producing Earth’s water.
    Your posting from incredulity and not taking into account the age of the earth combined with the vastly changing and mobile nature of the earths surface. erosion/deposition/tectonics/glaciation/forestation/aridation/etc all work at changing what we are seeing on a daily basis.
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    Quote Originally Posted by Suhail Jalbout
    Let us assume that the required 6.36 million comets, with 10 km diameter each, bombarded Earth to produce its water. The impact of each comet on the surface of Earth will form a crater with an area of at least 78.54 km2. Assuming that the comets fell side by side, they will cover an area of 500 million km2. Since the surface area of Earth is 510 million km2, this means 98% of Earth’s surface would be covered with craters. With all my due respect to your thoughts, I doubt the view that comets had the upper hand in producing Earth’s water.
    Studies of moon rocks show that the surface of the moon has been relatively inactive for about 3 billion years, meaning the heavy bombardment by comets, etc, ended at least that long ago (estimates put it at about 3.8 bya). This means that the same heavy bombardment of the Earth ended at about the same time. As Paleoichneum said, the craters left on the surface of the Earth at that time have since eroded away, because the surface of the Earth, unlike the moon's, has remained geologically active. That is why only a few of the more recent craters can still be seen on the surface of the Earth today.

    See: Chyba, Christopher. Seeding Earth: comets, oceans and life. The Planetary Report, Volume 10, Number 1 (January-February 1990):20-23, 30.
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    Paleoichneum wrote: “You’re posting from incredulity and not taking into account the age of the earth combined with the vastly changing and mobile nature of the earth’s surface. erosion/deposition/tectonics/glaciation/forestation/aridation/etc all work at changing what we are seeing on a daily basis.”

    The objective is to doubt the feasibility of the process. Whether few craters or none at all exist to our present day as a result of the dynamic activities of Earth is not of importance.


    Jsloan wrote: “Studies of moon rocks show that the surface of the moon has been relatively inactive for about 3 billion years, meaning the heavy bombardment by comets, etc”

    The “breccias” rocks are the result of a cataclysmic event that happened to the Moon between 3 to 3.5 billion years ago. These rocks were formed due to shattering of solid rock, melting then re-welding following an encounter with extreme and sudden heat. It is believed that huge asteroids, the size of cities, came crashing down on the Moon, heating, melting and welding rocks, and forming gigantic basins, mountains, and craters. I believe the cataclysmic period of the Moon occurred at the same time as the cataclysmic period of Mars. The explosion of Bode’s planet deformed the moons of Mars, evaporated its surface water, and created the “breccias” rocks on the Moon.
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    Ok Ok your right but what about the origin of water in the universe itself ???
    think from the start and u will get the answer by itself!!
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    Quote Originally Posted by Suhail Jalbout
    Let us assume that the required 6.36 million comets, with 10 km diameter each, bombarded Earth to produce its water. The impact of each comet on the surface of Earth will form a crater with an area of at least 78.54 km2. Assuming that the comets fell side by side, they will cover an area of 500 million km2. Since the surface area of Earth is 510 million km2, this means 98% of Earth’s surface would be covered with craters.
    Which over the course of 4.5 billion years on a geologically active planet with an atmosphere that, you know, dissolves rock, would be largely obliterated by erosion and tectonics. Not to mention the action of life forms such as plants. Seriously, have you really thought this through?
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    Quote Originally Posted by Suhail Jalbout
    The “breccias” rocks are the result of a cataclysmic event that happened to the Moon between 3 to 3.5 billion years ago. These rocks were formed due to shattering of solid rock, melting then re-welding following an encounter with extreme and sudden heat. It is believed that huge asteroids, the size of cities, came crashing down on the Moon, heating, melting and welding rocks, and forming gigantic basins, mountains, and craters. I believe the cataclysmic period of the Moon occurred at the same time as the cataclysmic period of Mars. The explosion of Bode’s planet deformed the moons of Mars, evaporated its surface water, and created the “breccias” rocks on the Moon.
    Okay, but that would have been before the bombardment stopped. I hope you understood the explanation I gave to answer your question about why we don't see many impact craters on Earth today (as compared with the moon).
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    Thebiologista wrote: “Which over the course of 4.5 billion years on a geologically active planet with an atmosphere that, you know, dissolves rock, would be largely obliterated by erosion and tectonics. Not to mention the action of life forms such as plants. Seriously, have you really thought this through?”

    As I have mentioned earlier, it is of NO IMPORTANCE if the craters were completely wiped out due to the dynamic activities of Earth. What is really important is the feasibility of having 6.36 million comets each having 209 billion tons of water covering 98% of Earth with craters is a feasible process or not. It is obvious and common sense to realize that the craters were wiped out. The record of craters on Earth goes back only to about 2.5 billion years ago.


    Jsloan wrote: “Okay, but that would have been before the bombardment stopped. I hope you understood the explanation I gave to answer your question about why we don't see many impact craters on Earth today (as compared with the moon).”

    I never asked “why we do not see many impact craters on Earth today”. Thank you for your contribution and comments.
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    Quote Originally Posted by Suhail Jalbout
    Thebiologista wrote: “Which over the course of 4.5 billion years on a geologically active planet with an atmosphere that, you know, dissolves rock, would be largely obliterated by erosion and tectonics. Not to mention the action of life forms such as plants. Seriously, have you really thought this through?”

    As I have mentioned earlier, it is of NO IMPORTANCE if the craters were completely wiped out due to the dynamic activities of Earth. What is really important is the feasibility of having 6.36 million comets each having 209 billion tons of water covering 98% of Earth with craters is a feasible process or not. It is obvious and common sense to realize that the craters were wiped out. The record of craters on Earth goes back only to about 2.5 billion years ago.


    Jsloan wrote: “Okay, but that would have been before the bombardment stopped. I hope you understood the explanation I gave to answer your question about why we don't see many impact craters on Earth today (as compared with the moon).”

    I never asked “why we do not see many impact craters on Earth today”. Thank you for your contribution and comments.
    In simple succinct sentences then, what is the point of your suggestion then, especially considering your response here:

    Quote Originally Posted by Suhail Jalbout
    Let us assume that the required 6.36 million comets, with 10 km diameter each, bombarded Earth to produce its water. The impact of each comet on the surface of Earth will form a crater with an area of at least 78.54 km2. Assuming that the comets fell side by side, they will cover an area of 500 million km2. Since the surface area of Earth is 510 million km2, this means 98% of Earth’s surface would be covered with craters. With all my due respect to your thoughts, I doubt the view that comets had the upper hand in producing Earth’s water.
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    Quote Originally Posted by Suhail Jalbout
    What is really important is the feasibility of having 6.36 million comets each having 209 billion tons of water covering 98% of Earth with craters is a feasible process or not.
    It is entirely feasible. It is more than feasible, it is highly probable. What makes you think it isn't?
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    Quote Originally Posted by Suhail Jalbout
    Let us assume that the required 6.36 million comets, with 10 km diameter each, bombarded Earth to produce its water. The impact of each comet on the surface of Earth will form a crater with an area of at least 78.54 km2. Assuming that the comets fell side by side, they will cover an area of 500 million km2. Since the surface area of Earth is 510 million km2, this means 98% of Earth’s surface would be covered with craters. With all my due respect to your thoughts, I doubt the view that comets had the upper hand in producing Earth’s water.
    What if the comets were incorporated into the Earth while it was still forming in the Sun's accretion disc? Or burned up in the atmosphere to produce water vapour and so did not leave craters at all?

    Quote Originally Posted by Ophiolite
    Your argument is an argument from incredulity and of no consequence.
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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    Quote Originally Posted by Ophiolite
    It is entirely feasible. It is more than feasible, it is highly probable. What makes you think it isn't?
    First time visitor, was looking into this subject and came across this post.

    Just as a counter point to Ophiolite, taking into account the earth is 4.54 billion years, and the calculation by OP of 6.36 million comets, that's an average of 1 comet of 10km of diameter hitting the earth every 714 years.

    The volume of the oceans alone is 1.4 billion cubic kilometers.
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    You're missing the point. If we calculated the number of average-volume meteors it would take to account for the whole volume of the Earth, you would probably find that a similarly unrealistic frequency of collision would be required.

    Meteors and comets represent the remenants of the Early solar system, after planet formation occurred. What it tells us is that the Early solar system was abundant in silicates and metals (evidence preserved in meteors) and water and other volatiles (evidence preserved in comets). The fact that it is statistically unlikely for a body of water with a volume equal to the Earth's oceans is no more relevant than the fact that it is statistically unlikely for a planet the size of the Earth to form from material from the Asteroid belt.


    The fact is, water was abundant in our solar system around the time that the Earth formed, and probably for a significant time afterwards.
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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    Quote Originally Posted by Exer
    [Just as a counter point to Ophiolite, taking into account the earth is 4.54 billion years, and the calculation by OP of 6.36 million comets, that's an average of 1 comet of 10km of diameter hitting the earth every 714 years.
    As Drowsy Turtle has pointed out the flux rate of bolide impacts during the late stages of planetary formation would be considerably higher than this. In fact, with around 700 million years from Earth' formation to the end of the Heavy Bombardment Phase that requires an impact only once every 111 years. That really isn't difficult to envisage is it? the formation of the planetesimals form which the Earth was formed - objects about the size of Mars - took only 100,000 years and involved orders of magnitude greater numbers of collisions.
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    I'm having a hard time looking at the amount of needed strikes to make this feasible. Considering the same must have happen to all the other planets in our solar system.
    Especially on larger bodies which must have been struck much more frequently.

    That is a spectacularly large amount of comets needed!

    Relatively speaking, we have currently detected a very small number of comets.

    I'm not saying it's not feasible, but neither is OP's suggestion. We know so very little of the origin of our planet and even less of our solar system. Both theories could very well be correct.
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    Quote Originally Posted by Exer
    I'm having a hard time looking at the amount of needed strikes to make this feasible. Considering the same must have happen to all the other planets in our solar system.
    Especially on larger bodies which must have been struck much more frequently.

    That is a spectacularly large amount of comets needed!

    Relatively speaking, we have currently detected a very small number of comets.
    Recap: the comets we see today are the remains of the early solar system, after planet formation. I think it would be fair to say that the comets which were involved in planet formation/ocean formation are no longer to be found floating around the solar system independantly, don't you?
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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    Quote Originally Posted by Exer
    I'm having a hard time looking at the amount of needed strikes to make this feasible.
    Your ignorance of the planetary formation process is not a solid objection to the number of impacts that doubtless took place. Why do I say you are ignorant of the planetary formation process? Well, there is this:

    Quote Originally Posted by Exer
    We know so very little of the origin of our planet and even less of our solar system. Both theories could very well be correct.
    This is consumate ignorance. We know an enormous amount about the mechanics and chemistry of the formation of the solar syste. True, there is much detail still to be derived, but to say we know very little is simply wrong.

    This handful of examples, taken from hundreds of instances, illustrate the range of topics and depth of understanding that exists.

    http://www.jstor.org/pss/10.1086/655775
    http://iopscience.iop.org/0004-637X/707/1/79/
    http://www.annualreviews.org/doi/abs...rnalCode=astro
    http://iopscience.iop.org/0004-637X/683/1/479/
    http://adsabs.harvard.edu/cgi-bin/np...k_type=ARTICLE
    http://www.nature.com/nature/journal...ture06086.html
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    The fact that we can't prove that the water alone came from just comets, shows that we don't know everything about the formation of our planet. It is just a theory at this stage.

    I take offence at you saying I'm ignorant. Feel free to discuss the topic but to stoop to a level of personal attack is uncalled for.

    OP might very well be partly correct, or another theory might present itself in a few years. This has been shown to be true on so many occasions.

    Until you can conclusively present undeniable proof that ALL of our water came from comets, I would suggest you keep you tone a little more civil.
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    Let me look at the debatable issue from a different angle. The hypothesis that the major part of Earth’s water originated from comets is implausible. This is based on the assumption that not all of the estimated 6.36 million comets that bombarded Earth had the same deuterium-to-hydrogen ratio as our oceans. Most probably they originated from different parts of our solar system. The measurements of the isotope ratios of hydrogen in the three comets Halley, Hyakutake, and Hale-Bopp by researches such as David Jewitt were approximately double that of our oceanic water. So how it is possible to explain how this huge number of comets could produce oceans with an earthly D/H ratio? On the other hand, the ring which was orbiting Earth before it collapsed most probably had the same D/H ratio as our oceans.
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    Quote Originally Posted by Exer
    The fact that we can't prove that the water alone came from just comets, shows that we don't know everything about the formation of our planet. It is just a theory at this stage.
    If you're going to debate scientific topics, you'll need to learn some scientific language. Saying something is 'just a theory' basically announces to us that you don't know what 'theory' means in a scientific context.

    Some light reading:

    http://en.wikipedia.org/wiki/Scientific_theory

    Quote Originally Posted by Exer
    I take offence at you saying I'm ignorant. Feel free to discuss the topic but to stoop to a level of personal attack is uncalled for.
    What exactly do you think 'ignorant' means? It's not really an insult. Ophiolite is suggesting that you appear to lack some knowledge (which is nothing to be ashamed of unless you fail to acknowledge it or refuse to try and learn). Knowledge is not a personality trait. Intelligence is, and whilst sometimes knowledge is a function of intelligence, this is not always so. Everyone is ignorant of some body of knowledge (for example, I am largely ignorant of vast tracts of physics and cosmology). Ophiolite has not called you stupid, nor has he implied anything else negative about you personally. I think you've taken offence inappropriately.

    Quote Originally Posted by Exer
    OP might very well be partly correct, or another theory might present itself in a few years. This has been shown to be true on so many occasions.

    Until you can conclusively present undeniable proof that ALL of our water came from comets, I would suggest you keep you tone a little more civil.
    It's not up to Ophiolite to do any such thing. The burden of evidence is always on the guy with the new idea. His tone has been civil thus far, so I'd appreciate it if we could move beyond the silly posturing and get to that evidence.
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    Quote Originally Posted by Exer
    The fact that we can't prove
    ... Is a fundamental axiom of science.


    All scientific theories are based on a certain amount of assumptions.

    In this case, we are assuming that the solar system formed in a certain way (producing an accretion disc in which planets can form). This is an assumption that we can justify by looking at evidence from newly-formed and currently-forming solar system elsewhere in the galaxy.

    We are also assuming that the majority of the material in the solar system has been here since 4.6 billion years ago when it formed - i.e. comets and meteors fairly accurately represent the composition of the early solar system.

    Lastly, we are making the typical set of assumptions that the laws of physics worked the same then as they appear to now, etc.
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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    Exer,
    here are several points.

    1) Ignorance. We are all ignorant. The number of things I do not know, even just compared with what humans en masse know, is many, many orders of magnitude greater. The more we know, the more ignorant we know we are. (I consider any day in which my percieved ignorance does not increase is a day wasted.)

    You are deeply ignorant of the current state of knowledge of planetary formation. That is a demonstrable fact: you have demonstrated it. There is little I can do if you choose to equate this objective statement of fact with a personal attack. I hope my explanation of what I mean by ignorance resolves this for you.

    2)
    The fact that we can't prove that the water alone came from just comets, shows that we don't know everything about the formation of our planet.
    a) Science does not prove things: science assembles evidence that supports a particular hypothesis better than any other, to the point that no viable alternative seems to exist.
    b) I have never made the claim that all water came from comets. I specifically used the term bolide in an earlier post to cover the possibility that a proportion of the water came from asteroids. Jalbout's comments about isotope ratios are pertinent here, as is the probability that some of the water was derived from original oligarchs from which the Earth formed.
    c) Nowhere have I claimed that we knew everything about the formation of the planet. I was disputing your claim that "We know so very little of the origin of our planet and even less of our solar system."

    3)
    Until you can conclusively present undeniable proof that ALL of our water came from comets, I would suggest you keep you tone a little more civil.
    There is a very substantial body of evidence pointing towards the Earth's water being derived in large part from bolide impacts. There is little or no evidence supporting the alternative proposal made by the OP. My civility or lack of it will have no impact on these facts.
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