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The capture model has the same problem. Even with a supercomputer to direct it, the operation of capturing a satellite moon, and retaining it, requires quite extraordinary precision.
In 1981, W.K. Hartman came up with what was at first considered an outlandish proposal. He had a body of about Mars size collide with the Earth in a glancing blow. The dust cloud that developed was mainly from the crustal material of the Earth, and, from that, the Moon was formed by accretion.
The heat generated by the impact drove off all the water from what was to form Moon rocks. The impact occurred after iron and other heavy elements had gravitated towards the center of the early molten Earth, thus accounting for the moon's iron deficiency. The model explains the density match between the Moon and the Earth's crust, the Moon's volcanic activity that gave the lava flows, and it readily accounts for the very large amount of radiometric data collected.
The hypothesis has the time of collision at more than 4 billion years ago with the subsequent accretion being relatively rapid. At the time of collision, the Earth was already close to full size.
The Urantia Book informs us that 2.5 billion years ago the Earth was 1/10th its present mass, and, up to 2 billion years ago, the Earth and Moon were much the same size, the Earth then being 1/5th its present size. The Earth then grew rapidly due to it capturing large space bodies.
The book says that 1.5 billion years ago, the Moon was at about its present size and the Earth was 2/3 rd the final size it attained about 1 billion years ago. These data are plotted in Figure 1 below. The decrease in the mass of the Moon is because it is given as being 1/5th the Earth's final size 2 billion years ago, and attaining its present size by -1.5 billion years. Currently the mass of the Moon is about 1/80th that of the Earth. In the second section of Fig. 1, we assume the size comparison was meant to be in terms of radius rather than the mass as this removes the anomaly of the moon's collapse.
The Urantia Book tells us that 1.5 billion years ago the Earth was a fiery furnace, then for thousands of years was enveloped in a cloud of steam such that the sun never shone on its surface.
By 1 billion years ago an ocean and a land continent appeared but the atmosphere was virtually devoid of oxygen until later generated by the sea weeds and other forms of vegetable life. Reconciling this whole scenario with the available data would, I think, be quite impossible.
For example, the book's version has the mass of the moon doubling between 2.5 and 2.0 billion years ago. The Apollo missions found that those vastly extensive mares (seas) we can see from Earth are composed of the basalt from lava flows that date back 3.1 to 3.9 billion years. According to the book's version, they should be buried under hundreds of miles of accreted materials.
On Earth, modern geology has shown the existence of stromatolites on at least three continents. These quite unique structures of limestone are known to be formed by blue green algae, and date back as far as 3.5 billion years ago. This surely is strong evidence for the existence of oceans at those times. These organisms are photosynthetic, the by-product of their chemistry being oxygen.
Initially this oxygen would have been mopped up by the excess iron dissolved in sea water and then precipitated as the ferric form of iron. The deposits from this process are found at places such as Isua in Greenland, and date back to 3.8 billion years ago. Sulfides also acted as oxygen acceptors, being deposited as 3.5 billion year old sulfate deposits (barite/gypsum) at places like Pilbarra in Western Australia. This deposition of oxidized minerals would have
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