Noble gases are so called because, like the nobility, they do nothing. You might also call them rare gases, because they are so rare on Earth as to be nearly nonexistent. The one exception is argon, which we inhale as 1 per cent of every breath, though it has no effect on our bodies whatsoever. Helium, neon, argon, krypton, xenon and radioactive radon are odourless, tasteless, practically non-reactive wisps of unconnected atoms. In this material universe, they amount to just about nothing at all. And yet... it would be hard to make a case that any other group of elements has had a greater impact on our understanding of the universe. For example, Darwin's theory of evolution needs an Earth many millions of years old in order for it to have had time to work. Yet the Bible placed a limit on Earth's age at a mere 6000 years. How was this argument resolved? The answer was helium, which is generated in rocks containing uranium and thorium.
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