Also, I see that for some reason there is continuing controversy about my use of the word 'nuclear reactions' to describe the nuclear decay processes that are keeping the interior of the earth warm.
Yes, I could have been more specific by saying 'decay processes' rather than just 'reactions'. Nuclear reactions include not only various decay processes, of course, but also fission and fusion. A one word post claiming the fact was "False." is a strange way to make this clarification, but whatever.
But, the real reason I'm posting is to give the following awesome and relevant fact: Although the vast majority of warming of the Earth's interior is from decay processes, there actually *are* fission processes taking place in the earth's interior!
There are examples involving several tons of uranium, and which were ongoing for ~10,000 years. Pretty freakin awesome!