The other day I got into an argument with a friend who's a Christian and he claimed it can be proved the moon is only 12,000 years old (thus bolstering creationist claims about evolution) by the amount of meteoric dust on its surface. He said that some scientists have calculated that if the moon were really billions of years old it would have five feet of dust surrounding its surface features. However, when Neil Armstrong stepped on the moon in 1969, there was only one inch of dust! What's the scoop?
George W., Baltimore
There’s a lot more than one inch of dust on the moon; Armstrong only sank in one inch, which is a different matter. After all, you only sink into loose beach sand about an inch, although it’s certainly a lot deeper.
The surface of the moon is composed primarily of debris called "regolith," which is from 36 to 60 feet deep and consists of boulders of varying size intermixed with dust. Most of the material is made up of lunar rock shattered by meteorites; the remaining 1 to 2-1/2 percent is the pulverized remnants of the meteorites themselves. Much of the dust is in the form of tiny glass spheres created in the heat of the meteorite impact. Dating of lunar samples has established the age of the moon at about 4.6 billion years.
Don’t expect this to convince your friend. Sounds like the only that would change his mind is a miracle.
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