In this chapter, Kean starts off with a basic but important question; "Where do elements come from?". For a long time it was thought that elements are just are and that they can not be created or destroyed. Later in the 1930s, the first theory was that all the matter in the universe came from a small speck that created a massive explosion that we call the big bang theory. However, this did not prove the reason why some stars only contain hydrogen and helium while others contained a lot more elements. Later, in the mid-1950's scientist explained the theory of stellar nucleosynthesis in a paper they named, B2FH. B2FH purposed that the universe was once mainly made up of hydrogen with a bit of helium and lithium. Then hydrogen will clump together to make a star, helium will then form by the gravitational pull which will power the star, or sun in the case of our solar system. However some stars die out when they run out of helium to fuse in their cores, hence white dwarfs. Some stronger and hotter stars will burn elements only up to iron. The reason for this is that fusing iron costs energy. The star will eventually implode and explode into a supernova that can last to about a month.
Kean then describes of the gas giant in our solar system, Jupitar, that was created when eruptions from the sun blew lighter elements to the "fringes". What makes it so interesting, according to Kean, is that a quarter of the helium that is normally found on a planet is missing from Jupitar along 90% of the neon. It's oceans of black liquid metallic hydrogen also make it very interesting because it can explain its weird magnetic field. Kean describes Jupitar as a failed planet which is why elements are so weird inside of Jupitar.
Kean then introduces Clair Patterson who also worked on the Manhattan Project. He knew the rate at which uranium breaks down and the 3 types of lead and he also knew that uranium only breaks down two of those types. He figured out that if he could find the difference between the ratio that is now to that of what it was originally then he could use uranium decay to find year zero. Luckily iron and uranium don't mix, even though iron and lead do. Meteors contained the same ratio of lead as they originally did and no uranium was around at the time. However his only problem when obtaining a meteor was, industrialization. A lot of lead came from paint, pipes, and even food that it contaminated Patterson's work. So after a thorough clean of his laboratory he came up with the best estimated for the age of the earth, 4.55 billion years. Kean then concludes with the idea that "we are all star stuff" and that unfortunately the discovery of new minerals can inspire greed in war and commerce.
What I liked most about this chapter was that I learned a lot more on how the stars and basically how the whole universe is made, or how we thing it is made. The only thing I didn't like about this chapter was that I was a bit confused on how supernova's are formed but I still thought it was interesting. I learned that that the big red dot on Jupitar's surface is actually a big storm that never stops which is also one thing I'd tell a friend. Overall, like the rest of the chapters, I really liked it.
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