Moon Quiz Winner


Originally published in Creation 3, no 4 (November 1980): 19-20.

Can You Prove How Young the Moon is?

That was the question and now here is the best presented of the answers. Congratulations to Alex Williams in the Environmental Science Division of the Australian Atomic Energy Commission.

But just to refresh your memories again here are the detailed questions and background.

When rocks were brought back from the moon a substance called neptunium was discovered to be present in them. Neptunium, a radioactive element has not been found to occur naturally on earth although it can be manufactured in the laboratory. Scientific literature sometimes uses this data to “prove” that the world must be very old, since if the earth were young, neptunium should exist naturally. This argument sounds logical and has widespread acceptance.

According to Evolutionary Cosmology the moon is at least as old as the earth (a believed 4.6 billion years). Therefore to be consistent neptunium on the moon creates interesting problems for those who adhere to a belief in an old age for the earth. We hope you can solve them!

Question (1) If Np is present on the moon, can the moon be 4.6 x 109 years old as commonly claimed?

Question (2) What would be the best argument against using the Np on the moon as proof that the moon was young, i.e. could the Np have another origin, i.e. meteoric bombardment, so that it is not part of the original moon, etc. Explain your case in no more than 500 words. (quoted from Ex Nihilo Vol. 3:2)

Dear Sirs,

The answers to the questions in “Can you prove how young the moon is?“ Ex Nihilo 3:2, 1980, are as follows:

1. No. the limit of detection of the appropriate nuclear analysis technique is at most in the order of:

10-15 to 10-20 g.

If the moon were 4.6 x 109 years old then the maximum possible concentration of Np in the present day moon would be:

8.3 x 10-604/8.3 x 1022 = 10-626g/kg., and would not be detectable.

2. There are several possible arguments that might explain the presence of Np on the moon without recourse to a young age explanation. Which argument is best can only be judged on information not supplied in the article.

First, small amounts of Np are formed by neutron capture in uranium minerals; thus small quantities occur naturally in the earth’s crust and would also occur naturally in the moon’s surface.

Second, several types of contamination may have occurred. Meteoric dust is a possible source but it would have to come from within the solar system and would require its own explanation. Human contamination is also possible. This could come from the sampling or analysis procedures, from exhaust gases or particulate material emanating from the space craft, or from space craft of earlier human origin that have disintegrated or otherwise contaminated the lunar surface. Some space craft use plutonium power sources and these would contain some neptunium.

A third possibility is that the moon was captured recently by the sun and had its origin in a nearby young star which still contained measurable quantities of Np.

To decide which, if any, of these arguments is plausible, the following further information is required:

  1. the concentration of Np in moon rocks in comparison with that in earth rocks.
  2. blank sample analyses to check for contamination in the sampling and analytical procedures.
  3. the location of lunar sampling sites in relation to possible contamination from other earth craft, and in relation to the craft which collected the samples.
  4. astronomical evidence for or against there being a nearby young star that could be the origin of the moon.

Editor’s Comment: We hope Alex is enjoying his win of one Genesis Record, one Strongs Concordance, one Myths & Miracles and one History of the World in Christian Perspective. For those of you who missed out, thanks for entering and try again next time.


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