Lunar radioactivity

Creationists claim that, because the moon contains radioactive elements and "short-lived" isotopes, it cannot be old.
==Isotopes==
Evolution-Facts.org maintains, as of 2016:Evolution Encyclopedia Vol. 1: CHAPTER SIX THE AGE OF THE EARTH (see #21 - Lunar isotopes)
This is immediately incorrect. 230Th has a half-life of 75,380 years, and 236U has a half-life of 23,420,000 years. In 50,000, there would still be more than half (63.1%) of the original 230Th and almost all (99.85%) of the 236U. Even beyond this, we can expect measurable amounts of anything to hang around for about 10 half-lives, which pushes 230Th to 753,800 years, and 236U to 234,200,000 years.Is the Earth Young?
Kent Hovind wrote:
R. L. Wysong 1976 writes:Wysong, R. L., 1976. The Creation-Evolution Controversy, Midland, MI: Inquiry Press, pp. 177-178.CF220, Mark Isaak, Talk Origins
Indeed, if the Earth and Moon are indeed 4.5 billion years old, no trace of the original supply of those isotopes should now exist.
Where does the 230Th come from? The most abundant uranium isotope is 238U, about 99.275% of natural uranium.How Good Are Those Young-Earth Arguments? 238U decays until it ends up as 206Pb, lead. 238U has a half-life of 4,468,000,000 years, already long enough to be compatible with an old moon. Creationists assume that the 230Th had to be there from the beginning, but instead 230Th is continuously created.
Where does the 236U come from? The next most abundant uranium isotope is 235U, about 0.7% or 0.72% of natural uranium. 235U has a half life of 703,800,000 years, but using the 10 half-life criterion, measureable amounts should hang around for about 7,038,000,000 years, again long enough for an old moon. The lunar surface is directly exposed to solar wind and other sources of cosmic rays.Radioactive Moon 235U will turn into 236U by absorption of a single slow neutron, which can be supplied directly by solar wind or as a by product of a solar wind proton colliding with the lunar surface. Creationists assume that the 236U had to be there from the beginning, but instead 236U is continuously created.
Thus, the Th-230 and U-236 we see on the Moon are of recent origin, not part of the Moon's primordial supply, and therefore do not constitute evidence for a young Earth.
Even CreationWiki agrees that this is a bad argument.Short-lived isotopes Th-230 and U-236 exist on the moon
==Radioactivity==
Evolution-Facts.org maintains, as of 2016:http://www.tim-thompson.com/young-earth2.html#number21
Kofahl et al. 1975 wrote:R. E. Kofahl and K.L. Segraves, The Creation Explanation (1975), p. 145.
Yet radioactivity is the direct product of the breakdown of short half-life isotopes; as long as there is a source for these radioisotopes (and such a source was proven above), then there is no issue here.
==See also==
*Rotation of the Earth (the Earth's spin is running down too fast)
*Lunar recession (the moon is going away from the Earth too fast)
*Lunar dust (there's not enough moon dust)
*Lunar formation (the moon couldn't have formed)
*Lunar atmosphere (there's too much moon gas)
*Lunar bukkake hypothesis (the moon got shot with water during the Flood)
==References==
Category:Creationist claims
Category:Moon