Lunar radioactivity

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Creationists claim that, because the '''[[moon]]''' contains '''radioactive''' elements and "short-lived" isotopes, it cannot be old.

==Isotopes==
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Evolution-Facts.org maintains, as of 2016:<ref name=EF>[https://archive.is/TERIZ Evolution Encyclopedia Vol. 1: CHAPTER SIX  THE AGE OF THE EARTH] (see #21 - Lunar isotopes)</ref>

{{cquote|One of the most surprising moon rock discoveries is seldom mentioned: Short-lived Uranium 236 and Thorium 230 were found in those stones! Short-term radioactive isotopes do not last long; they rather quickly turn into their end product, which is lead. If the moon were even 50,000 years old, these short-life radioisotopes would long since have decayed into lead. But instead they were relatively abundant in the moon rocks! The importance of this should not be underestimated. The moon cannot be older than several thousand years.}}

This is immediately incorrect. <sup>230</sup>Th has a half-life of 75,380 years, and <sup>236</sup>U has a half-life of 23,420,000 years. In 50,000, there would still be more than half (63.1%) of the original <sup>230</sup>Th and almost all (99.85%) of the <sup>236</sup>U. Even beyond this, we can expect measurable amounts of anything to hang around for about 10 half-lives, which pushes <sup>230</sup>Th to 753,800 years, and <sup>236</sup>U to 234,200,000 years.<ref name=Tim>[http://www.tim-thompson.com/young-earth2.html#number20 Is the Earth Young?]</ref>

Kent Hovind wrote:<ref name=Tim />

{{cquote|The Moon contains considerable quantities of U-236 and Th-230, both of which are short-lived isotopes that would have expired long ago if the Moon were 4.5 billion years old.}}

R. L. Wysong 1976 writes:<ref>Wysong, R. L., 1976. The Creation-Evolution Controversy, Midland, MI: Inquiry Press, pp. 177-178.</ref><ref>[http://www.talkorigins.org/indexcc/CF/CF220.html CF220], Mark Isaak, [[Talk Origins]]</ref>

{{cquote|Th-230 and U-236 exist on the moon. But these isotopes are so short-lived that we would not expect any still to be around if the moon were billions of years old.}}

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 <sup>230</sup>Th come from? The most abundant uranium isotope is <sup>238</sup>U, about 99.275% of natural uranium.<ref name=HowGood >[http://www.talkorigins.org/faqs/hovind/howgood-yea.html#proof6 How Good Are Those Young-Earth Arguments?]</ref> <sup>238</sup>U [[radioactive decay|decays]] {{wpl|Decay_chain#Uranium_series|through a series of different nuclei, including <sup>230</sup>Th}} until it ends up as <sup>206</sup>Pb, lead. <sup>238</sup>U has a half-life of 4,468,000,000 years, already long enough to be compatible with an old moon.<ref name=Tim /> Creationists assume that the <sup>230</sup>Th had to be there from the beginning, but instead <sup>230</sup>Th is continuously created.

Where does the <sup>236</sup>U come from? The next most abundant uranium isotope is <sup>235</sup>U, about 0.7%<ref name=HowGood /> or 0.72%<ref name=Tim /> of natural uranium. <sup>235</sup>U 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.<ref name=Tim /> The lunar surface is directly exposed to solar wind and other sources of cosmic rays.<ref>[http://science.nasa.gov/science-news/science-at-nasa/2005/08sep_radioactivemoon/ Radioactive Moon]</ref> <sup>235</sup>U will turn into <sup>236</sup>U 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 <sup>236</sup>U had to be there from the beginning, but instead <sup>236</sup>U 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.<ref>[http://www.en.creationwiki.org/Short-lived_isotopes_Th-230_and_U-236_exist_on_the_moon_(Talk.Origins) Short-lived isotopes Th-230 and U-236 exist on the moon]</ref>

==Radioactivity==
Evolution-Facts.org maintains, as of 2016:<ref name=EF /><ref name=Tim21>http://www.tim-thompson.com/young-earth2.html#number21</ref>

{{cquote|Rocks brought by Apollo teams from the moon have been dated by the various radiometric methods. A variety of very conflicting dates has resulted from these tests (see chapter 7, Dating Methods, for a discussion of this). But the factor of relatively high radioactivity of those rocks indicates a young age for the moon[.]}}

Kofahl ''et al.'' 1975 wrote:<ref>R. E. Kofahl and K.L. Segraves, The Creation Explanation (1975), p. 145.</ref>

{{cquote|The content of radioactive elements in the moon rocks is so high that if the moon were actually millions of years old, the heat produced by radioactive decomposition would have melted the moon.}}

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.<ref name=Tim21 />

==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==
{{reflist}}

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[[Category:Creationist claims]]
[[Category:Moon]]

Categories: Creationist claims, Moon