Argument 50 彗星 海洋水的来源 球拍 留链接必回

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Argument 50 From a draft textbook manuscript submitted to a publisher.

"As Earth was being formed out of the collision of space rocks, the heat from those collisions and from the increasing gravitational energy of the planet made the entire planet molten, even the surface. Any water present would have evaporated and gone off into space. As the planet approached its current size, however, its gravitation became strong enough to hold gases and water vapor around it as an atmosphere. Because comets are largely ice made up of frozen water and gases, a comet striking Earth then would have vaporized. The resulting water vapor would have been retained in the atmosphere, eventually falling as rain on the cooled and solidified surface of Earth. Therefore, the water in Earth's oceans must have originated from comets."


Body:
In this argument, the arguer advocates that the water in Earth's oceans must have originated from comets. Although, on the surface, this argument might be reasonable, it is in fact ill-conceived. The reason is stated as below.

In the first place, the arguer assumes that the heat from collision and the increasing gravitational energy of the planet made any water evaporated and gone into the space. Although the statement may entirely impossible, the arguer overlooks another possible condition which generates a opposite result. It likely that the immense energy and heat speed the efficiency of chemical reaction which water takes part in, and eventually gets into stasis. The stable state prevents evaporating. Unless the arguer rulls out this completely possible situation, the claim remains unfounded.

At second place, the arguer assumes that as the planet approached current sizes, the gravitation is able to hold gasses and water vapor around it as an atmosphere. Even if arguer’s assumption that gravitation has the ability to hold gases and vapor is correct, it must make accurate confine of the size which the gravitation effect. Additionally, when a collision really happens, the ability to hold gases and vapor cannot be ensured. Without, sufficient evidences, I cannot approve of this claim.

At third place, the arguer assumes that comets are largely made up of frozen water and gases. Although outer space is a condition with high pressure and low temperature, it is arbitrary to assume that comets mainly consist of frozen water and gases. If there is no water existing in comets, is unnecessary to discuss dispute. Lacking sufficient and accurate evidence and data about the chemical composition of the comets, the arguer cannot convince me the water of Earth’ oceans originated from water.


At last place, the arguer assumes the water retained in atmosphere eventually falling as rain on the surface. However, the argument provides no evidence about possibility of the water from comets flows into oceans. It is entirely possible that the water flows in underground. Thus, if the arguer cannot exclude the situation that water from comets flow into underground, the statement is still unfounded.

In summary, the arguer draws a hasty conclusion with inadequate evidence supporting about the temperature in collision, the size of Earth ensure gravitation can hold the gasses and vapor, the chemical composition of comets and possibilities that water flows into underground, and finally fails to recognize that the water in Earth's ocean must have originated from comets.