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→Honest question from a frustrated user
:: Andy, I don't think you should let him change a thing. It is a really, really good article as is everything you contribute to this site. Your students are very lucky to have you. --[[User:Jack|Jack]] 19:26, 18 March 2007 (EDT)
:: Andy, I don't think you should let him change a thing. It is a really, really good article as is everything you contribute to this site. Your students are very lucky to have you. --[[User:Jack|Jack]] 19:26, 18 March 2007 (EDT)
::Let's see... I didn't read into your more recent changes, but let's start with a few cases of ''conveniently'' selective quoting:
{{QuoteBox|Three such tests are discussed here. None of these is supportive of the Giant Impact model, '''but neither do they disprove it'''.}}
{{QuoteBox|Unfortunately, researchers have had trouble getting the giant-impact model to work without the contrivances that scuttled earlier theories. "Putting enough material into orbit to form the moon seemed to require a rather narrow set of impact conditions," says Robin M. Canup of the Southwest Research Institute in Boulder, Colo. '''But a new study by her and Erik Asphaug of the University of California at Santa Cruz may have broken the logjam.'''}}
{{QuoteBox|Four facts and three parameters is a recipe for contradiction. To explain the moon's low iron content, you need to avoid a grazing collision (corresponding to a large impact angle), lest too much of the impactor's iron spill into orbit. Then, to explain the angular momentum, you need to compensate for the smallish angle with a hefty impactor. Then, to explain the moon's mass, you need to adjust the proto-Earth's mass. In the end, you might find that the total mass is incorrect.<br>
<br>
In 1997 Alastair G. W. Cameron, one of the fathers of the giant-impact theory, now at the University of Arizona, arrived at a total mass that was a third too low. He suggested that subsequent asteroid impacts made up the difference. But few liked the idea, as the asteroids would have added extra iron.<br>
<br>
'''Canup and Asphaug argue that the fault lies not in the stars but in our simulations.''' The calculations rely on a technique known as smoothed-particle hydrodynamics, which subdivides the bodies and applies the laws of physics to each piece. Early runs tracked 3,000 pieces--leaving the iron core of the moon to be represented by just a single piece. Even the slightest computational imprecision could vastly overstate the iron content, in which case the computer compensated by reducing the impact angle. The result was a bias toward heavy impactors and light proto-Earths. '''Because Canup and Asphaug use 30,000 particles, they get by with a much smaller impactor. Everything--mass, iron, momentum--clicks into place.'''}}
::I'm not trying to say that there are no problems with the theory (and criticism should be mentioned in the article, of course), but you try to make things look as if scientists only cling to a completely silly theory that has been effectively disproven already.
::The only thing I credit you for is the omission of any overly "Of course, the only truth is that God created the Moon during Creation Week, and Answers in Genesis shows undeniable proof." bias... yet.
::An attempt to balance things would begin with a rewrite the condensed list with things that speak for the impact theory (which you "expanded" by a slightly biased view of the events leading to it - you really couldn't resist inserting the "non-creationist scientists" bit, could you?).
::Don't get me wrong, I'm not trying to create an ultra-super-"Why that theory has been proven without doubt!" article. I just want a bit of fairness and a bit of style correction to make the article look halfway presentable. --[[User:Sid 3050|Sid 3050]] 19:51, 18 March 2007 (EDT)