Science: The leading theory for the Moon’s formation is that Earth and a Mars-sized planet collided some 4.5 billion years ago and produced a disk of magma that orbited Earth and over time coalesced to form the Moon. If so, say researchers, the Moon’s chemical composition should reflect that of both Earth and the other planet. However, studies of lunar rocks collected by the Apollo missions in the 1970s have cast doubt on that theory. Previous research established that the Moon’s oxygen isotope composition is indistinguishable from that of Earth. Now, according to a study published yesterday in Nature Geoscience by Junjun Zhang of the University of Chicago and colleagues, another isotope ratio, that of titanium-50 to titanium-47, has been shown to be similar on both Earth and the Moon. Although the oxygen finding can be explained because oxygen vaporizes easily and could have been exchanged between Earth and the newly forming Moon, titanium does not vaporize as easily. Despite the new evidence, Zhang does not completely rule out the earlier theory: “Our study cannot provide a definite answer to the origin of the Moon yet. The message we hope to convey is that isotopic homogeneity between the Earth and Moon is a fundamental new constraint on the evolution of the Earth–Moon system.”
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Lunar origin has been a classic example of what happens when religion gets in the way of science. Capture is the one model that matches the facts. It always did match the facts and it matches them now, if we simply assume that quantities of material from a common source — presumably another planet — found their way to both Earth and Moon. Capture has been around almost since geology has been around and so has the idea of capture in association with the pre-cambrian/cambrian unconformity (approx. 540 mill.yrs past) . This event was necessary to the so-called “cambrian explosion” of life. No, the silvery moon did not come loaded with trilobites, brachiopods and sea-scorpions, the mechanical outcome of its capture and associated events produced intense quantum computational outcomes which had the desired and planned effect of causing the seas to teem with complex life. Species have to do with quantum information. It’s in the Bible — but you don’t require a Bible to see the obvious.
P. Goldreich, with Gerstenkorn’s input, got close to having it solved in 1972 (SCIENTIFIC AMERICAN) and A.E. Ringwood showed the problems with giant impact and got the close Earth similarity not a lot of years after APOLLO concluded (EARTH AND PLANETARY SCIENCE LETTERS).
Why was Capture ruled out?