| CommonNinja said:
Which begs the question "how did so much Uranium get here through fusion?" It is simply hard to believe that fusion could have created each and every element on the periodic table, and then some how a star exploded all of thoese elements onto earth. Also, if the earth really is billions of years old, wouldn't most of the uranium that came from the supernovas alreay have decayed into Thorium? Uranium has a half life of about 4 Billion years, which means around the time when the first lifeform was first forming, there would have had to have been at least twice the amount of Uranium on earth as there is today. Thats a lot of Uranium, especially if you believe it all came from fusion! |
"how did so much Uranium get here through fusion?"
I can't possibly know that, but my best guess is that earth just happened to be born close to where a supernovae had happened before.
"wouldn't most of the uranium that came from the supernovas alreay have decayed into Thorium?" / "would have had to have been at least twice the amount of Uranium on earth as there is today." Yes there was approxematley twice the amount, and yes that mostly decayed to thorium, but with thorium (Th234 the isotope that comes out of a U238 decay) having a half life of mere 24days (compared to the 4.5 billion years of U238) that has decayed just shortly after the uranium which produced it.
