Friday, September 5, 2008


I had a debate recently with a good friend of mine. It erupted after discussion about the recent nomination of Sarah Palin for Vice President. My friend was excited about the nomination, and I told him that I thought she was a nut-case. He asked me why, and I replied "She thinks the Earth is 6,000 years old."

He seemed stunned that I would say such a thing, and I was stunned that someone as smart as he is could even be sympathetic to an idea that is so idiotic and anti-progressive. He then spouted off about how carbon dating was inaccurate, after stating that he didn't believe that the Earth could be "millions and millions" of years old.

I hate getting into debates like this, but I had to use the courtroom analogy. Basically, I gave him a hypothetical courtroom situation in which he had to choose between evidence on one side, and hunch on the other. He refused to respond, and I told him that I thought the Flying Spaghetti Monster made the Earth at a ridiculous date only a few years ago, and that I was right because I "believed" it. That pretty much ended the touchy subject, and he proceeded to say that he's heard both sides and that he's made up his mind.

First of all, carbon dating can't be used to find the age of the Earth, as its half life is approximately 5,730 years. Carbon-14 dating is used almost solely for archaeological dating, and not ancient geological dating. Secondly, had he actually studied the issue beyond creationism, he would know that all scientists estimate the Earth to be more than "millions and millions" of years old; it is instead approximately 4.5 billion years old.

The best way to figure out the age of Earth is not carbon dating, but radiometric dating done with molecules that have much longer half-lives. Let me quote Wikipedia for you:

"Two other radiometric techniques are used for long-term dating. Potassium-argon dating involves electron capture or positron decay of potassium-40 to argon-40. Potassium-40 has a half-life of 1.3 billion years, and so this method is applicable to the oldest rocks. Radioactive potassium-40 is common in micas, feldspars, and hornblendes, though the blocking temperature is fairly low in these materials, about 125°C (mica) to 450°C (hornblende).

Rubidium-strontium dating is based on the beta decay of rubidium-87 to strontium-87, with a half-life of 50 billion years. This scheme is used to date old igneous and metamorphic rocks, and has also been used to date lunar samples. Blocking temperatures are so high that they are not a concern. Rubidium-strontium dating is not as precise as the uranium-lead method, with errors of 30 to 50 million years for a 3-billion-year-old sample."

In closing, I must say that I worry about the nomination of Palin, since if McCain wins, her opinion on the age of the Earth could end up being the "science" taught in our tax funded public schools.


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