Talk:John A. O'Keefe (astronomer)
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Origin of tektites
editFrom the John O'Keefe article of 3 Jan 07:
After the moon landings his claim was apparently supported by a chemical analysis of a portion of lunar sample 12013 retrieved by Apollo 12 astronaut Pete Conrad that showed a similar major element composition to some tektites found in Southeast Asia. Some Apollo 14 samples also had chemistries similar to tektites. However, most other lunar data strongly challenged the O'Keefe hypothesis, and almost all researchers in this field now accept that tektites are of terrestrial origin, the products of large meteorite or cometary impacts on Earth. This is supported by geochemical, isotopic and mineralogical evidence, and the fact that most tektite strewn fields can now be confidently matched to known impact craters of similar age on Earth [8,9]. Despite these facts, it should be noted that no impact crater associated with the massive 700,000-year-old Australasian tektite event has ever been found; undeniably, this single fact casts a nagging shadow upon the accepted impact model and is rarely mentioned when discussing tektites. Also, to compound the problem, craters associated with tektite strewnfields may be 'connate' (that is, not the source of the tektites by rather the by-product of the tektite event) as suggested in the 1970s by the late Dean R. Chapman of NASA. Several of O'Keefe's ideas about the physics of tektite formation, especially pertaining to Stokes' Law and the slow formation or 'fining' of tektites (apparently not possible in a rapid impact event), also remain as challenges to modern explanations of how tektites might have formed.
In my opinion a lot of this discussion about the origin of tektites doesn't really belong in this biographical article about John O'Keefe. The facts, from a biographical point of view, are that O'Keefe did a lot of research on tektites and strongly supported the lunar volcano theory of tektite origin, but that this theory steadily lost support from the rest of scientific community after the Apollo mission, and is now abandoned by probably all scientists working in this field. This in itself doesn't prove that O'Keefe was wrong, but debates about such theories and what facts do or don't support them would be better on the tektite page (or even it's discussion page). -Zamphuor 09:01, 3 February 2007 (UTC)